— GEOMETOR • elements

G.194 alternando (alternate ratio)

Alternate ratio means taking the:term:antecedent <G.181> in relation to the antecedent and the consequent in relation to the consequent.

G.195 magnitudes proportional proportional

If four magnitudes be proportional, they is proportional alternately.

G.201 whole whole part

If, as a whole is to a whole, so is a part subtracted to a part subtracted, the remainder is to the remainder as whole to whole.

If there be three magnitudes, and others equal to them in multitude, which taken two and two together are in the same ratio, and the proportion of them be perturbed, they is in the same ratio ex aequali.

G.213 equiangular triangles sides

In equiangular triangles the sides about the equal angles are proportional, and those are corresponding sides which subtend the equal angles.

G.231 similar triangles duplicate

Similar triangles are to one another in the duplicate ratio of the corresponding sides.

G.232 similar polygons divided

Similar polygons are divided into similar triangles, and into triangles equal in multitude and in the same ratio as the wholes, and the polygon has to the polygon a ratio duplicate of that which the corresponding side has to the corresponding side.

G.236 parallelogram parallelograms diameter

In any parallelogram the parallelograms about the diameter are similar both to the whole and to one another.

G.237 construct one and the same figure similar to

Construct one and the same figure similar to a given polygon and equal to another given polygon.

G.261 number part number

If a number be a part of a number, and another be the same part of another, alternately also, whatever part or parts the first is of the third, the same part, or the same parts, will the second also be of the fourth.

G.262 number parts number

If a number be parts of a number, and another be the same parts of another, alternately also, whatever parts or part the first is of the third, the same parts or the same part will the second also be of the fourth.

G.266 numbers proportional proportional

If four numbers be proportional, they is proportional alternately.

G.267 there many numbers

If there be as many numbers as we please, and others equal to them in multitude, which taken two and two are in the same ratio, they is in the same ratio ex aequali.

G.268 unit measure number

If an unit measure any number, and another number measure any other number the same number of times, alternately also, the unit will measure the third number the same number of times that the second measures the fourth.

G.270 numbers multiplying make

If two numbers by multiplying one another make certain numbers, the numbers so produced are equal.

G.271 number multiplying numbers

If a number by multiplying two numbers make certain numbers, the numbers so produced will have the same ratio as the numbers multiplied.

G.293 number measured number

If a number be measured by any number, the number which is measured will have a part called by the same name as the measuring number.

G.294 number part whatever

If a number have any part whatever, it is measured by a number called by the same name as the part.

G.319 similar plane numbers

Between two similar plane numbers there is one mean proportional number; and the plane number has to the plane number the ratio duplicate of that which the corresponding side has to the corresponding side.

G.321 similar solid numbers

Between two similar solid numbers there fall two mean proportional numbers; and the solid number has to the similar solid number the ratio triplicate of that which the corresponding side has to the corresponding side.

G.322 mean proportional number

If one mean proportional number fall between two numbers, the numbers is similar plane numbers.

G.340 many numbers please

If as many numbers as we please beginning from an unit be in continued proportion, the less measures the greater according to some one of the numbers which have place among the proportional numbers.

G.347 there many numbers

If there be as many numbers as we please in continued proportion, and the extremes of them be prime to one another, the last will not be to any other number as the first to the second.

G.401 find medial segments commensurable in square only which

Find medial segments commensurable in square only which contain a rational rectangle.

G.402 find medial segments commensurable in square only which

Find medial segments commensurable in square only which contain a medial rectangle.

G.446 segment commensurable length

A segment commensurable in length with a binomial segment is itself also binomial and the same in order.

G.447 segment commensurable length

A segment commensurable in length with a bimedial segment is itself also bimedial and the same in order.

G.448 segment commensurable major

A segment commensurable with a major segment is itself also major.

G.461 apotome only rational

To an apotome only one rational segment can be annexed which is commensurable with the whole in square only.

G.462 apotome medial segment

To a first apotome of a medial segment only one medial segment can be annexed which is commensurable with the whole in square only and which contains with the whole a rational rectangle.

G.489 segment commensurable length

A segment commensurable in length with an apotome is an apotome and the same in order.

G.499 square rational segment

The square on a rational segment, if applied to an apotome, produces as breadth the binomial segment the terms of which are commensurable with the terms of the apotome and in the same ratio; and further the binomial so arising has the same order as the apotome.

G.500 area contained apotome

If an area be contained by an apotome and the binomial segment the terms of which are commensurable with the terms of the apotome and in the same ratio, the “side” of the area is rational.

G.528 construct a solid angle out of three plane

Construct a solid angle out of three plane angles two of which, taken together in any manner, are greater than the remaining one: thus the three angles must be less than four right angles.

G.552 circles squares diameters

Circles are to one another as the squares on the diameters.

G.555 there pyramids height

If there be two pyramids of the same height which have triangular bases, and each of them be divided into two pyramids equal to one another and similar to the whole, and into two equal prisms, then, as the base of the one pyramid is to the base of the other pyramid, so will all the prisms in the one pyramid be to all the prisms, being equal in multitude, in the other pyramid.

Posts tagged 'alternando'