Question

(4a-9)^2 multiply and simplify completely

Answer 1

Answer:

$16{a}^{2}-72a+81$

Step-by-step explanation:

1) Use Square of Difference:${(a-b)}^{2}={a}^{2}-2ab+{b}^{2}.$

${(4a)}^{2}-2\times 4a\times 9+{9}^{2}$

2) Use Multiplication Distributive Property: ${(xy)}^{a}={x}^{a}{y}^{a}$

${4}^{2}{a}^{2}-2\times 4a\times 9+{9}^{2}$

3)  Simplify  ${4}^{2}$ to  16

$16{a}^{2}-2\times 4a\times 9+{9}^{2}$

4) Simplify ${9}^{2}$ to 81

$16{a}^{2}-2\times 4a\times 9+81$

5) Simplify  $2\times 4a\times 9$ to 72a.

$16{a}^{2}-72a+81$