Given: 4d=1/3(c-d) Proof= c=13d

Here, we are required to proof c = 13d from 4d=1/3(c-d)

Ultimately, c = 13d (proof)

We have;

Cross product

4d × 3 = c - d

therefore, By collecting like terms;

C = 12d +d

and Ultimately, c = 13d

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Proof:

Multiply both of the sides by 3. You would get 12d = c - d. Add d on both sides, and you would get c = 12d

b. 24 mm

step-by-step explanation:

use the pythagorean theorem.

a^2 + b^2 = c^2

a^2 + 7^2 = 25^2

a^2 + 49 = 625

a^2 = 576

a = 24

answer: b. 24 mm

just do 5.2 + 2 ( 7.2) and 1/3 x 3 (.9) and youv'e got your equation. 0.9( 9/10) + 7.2 ^2 = 16.4 hope i could !

step-by-step explanation: