since triangles are similar
4/x = 7x/7
=》 4/x = x
=》x^2 = 4
=》 x = 2
for right triangles a^2 = b^2+c^2
DF^2 = 7^2+2^2 = 53
=》 DF = 7.28
perimeter of DEF = 7 +2+7.28 = 16.28
A. -448
Explanation:
-28 times 16 is -448.
A) x= 5
b) x= 1
basically, 5x5x5=125 so that mean 5 to the power of 3 equals 125. This says x-2, so 5-2=3 which completes the equation of 5 to the power of 3. same with the second one.