You could substitute with 6 for x+9 and 9 for x+6 , otherwise it be 0=-3 or no solution
Lateral surface area, is the area that is not including bases
so it is an area of free rectangles
3*(5*8)=3*40=120 cm²
(85+90+80+100)/4 = 88.75. It's rounds off to 89
<u>Answer</u>
D.25x2 – 36
<u>Explanation</u>
A. x² – 16x + 64
product = 64
sum = -16
factors: -8 and -8
x² – 16x + 64 = x² - 8x - 8x + 64
= x(x - 8) - 8(x - 8)
= (x - 8)(x-8) = (x-8)² ⇒ Not a difference of squares
B.x² + 4 = (x² + 2²) ⇒ Not a difference of squares
C.9x² – x – 36
product = - 324
sum = -1
Factors: none
9x² – x – 36 ⇒ Has no perfect roots.
D.25x² – 36
25x² – 36 = (5x)² - 6² ⇒ This is the difference of squares.
