Use a special product formula to find the product. $( a - 4 b ) ^ { 2 }$
A) $a ^ { 2 } - 8 a b + 16 b ^ { 2 }$
B) $a ^ { 2 } - 4 a b + 8 b ^ { 2 }$
C) $a ^ { 2 } + 8 a b + 8 b ^ { 2 }$
D) $a ^ { 2 } + 8 a b - 16 b ^ { 2 }$
E) $a ^ { 2 } - 16 a b + 14 b ^ { 2 }$

Question

Quizplus · Accepted Answer

The special product formula for $(a-b)^2$ is $(a-b)^2=a^2-2ab+b^2$. Applying this formula to $(a-4b)^2$, we get $(a-4b)^2=a^2-2(a)(4b)+(4b)^2=a^2-8ab+16b^2$. So, the answer is A, $a^2-8ab+16b^2$.

Use a Special Product Formula to Find the Product (a−4b)2( a - 4 b ) ^ { 2 }(a−4b)2

Use a Special Product Formula to Find the Product $( a - 4 b ) ^ { 2 }$