18 + 81 = 9(x²<span> + 6x + 9)
</span><span>11 = (x + 3)</span>²
When we are completing the square, we are going to move the value of c across the equals. We will do that by adding, and end up with
18=9(x²+6x)
We take the value of b (the coefficient of x), divide it by 2 and square it:
(6/2)²=3²=9
This is the value that completes the square. However, since the entire square is multiplied by 9, this value must be multiplied by 9 before we can add it across the equals:
18+9(9) = 9(x²+6x+9)
18+81=9(x²+6x+9)
99=9(x²+6x+9)
Dividing both sides by 9, we have:
11=x²+6x+9
11=(x+3)²
Answer:
3. 122.025
4. 469.2
Step-by-step explanation:
16.27/2 =8.135
8.135*15= 122.025
11.73 divided by 1/2= 23.46
23.46*20=469.2
A is not congruent
B is not congruent
C is congruent
D is not congruent
E is congruent
Is congruent
