A triangle was dilated by a scale factor of 2. If cos a° = three fifths and segment FD measures 6 units, how long is segment DE?

10 units

Step-by-step explanation:

Given that:

Cos a = 3 /5

From trigonometry ;

Cos θ = Adjacent / hypotenus

Side Adjacent angle a = 3 = FD

Hypotenus = 5 = DE

3 / 5 = FD / DE

FD = 6 units

3/5 = 6/DE

DE * 3/5 = 6

DE = 6 ÷ 3/5

DE = 6 * 5 /3

DE = 30 /3

DE = 10 units

for this case we have the following expression:

to solve, we rewrite the expression as:

we apply double c and we have:

thus, the quotient is 48.

so, patel found a wrong ratio and the multiplication was incorrect.

option d