Question

ΔABC ​~ ΔDEC. ∠1 and ∠2 have the same measure. Find DC and DE.​ (Hint: Let DC=x and AC=x+3. Use the figure shown.)

Answer 1

DC/AC=EC/BC
x/(x+3)=10/16
10(x+3)=16x
10x+30=16x
30=6x
x=5
DC=x=5
DC=5 units long

10/16=DE/AB,     DE=y

10/16=y/10
16*y=10*10
y=6.25≈6.3
DE≈6.3