<span>x^2 + 8x = -3
</span><span>x^2 + 8x + 16 = -3 + 16
using a^2 + 2 a b + b^2 = (a+b)^2
</span><span>
</span>x^2 + 8x + 16 = 13
<span>(x +4)^2 = 13
answer : 16 is the number </span><span>you must add to complete the square</span>
Answer:
4
Step-by-step explanation:
7. the last one
I = P R T
I = 15.75 P = 500 R = unknown T = 6
15.75 = 500 (r) (6)
divide the T and I
15.75 ÷ 6 = 500 (r) (6) ÷6
2.62 = 500 (r) *get rid of the six*
divide the P with new answer
2.62 ÷ 500 = 500 ÷ 500 *get rid of 500*
0.00524 = r
move decimal to make it in to a percentage
5.24% = R
I believe your answer is 6 seconds.
Because the height of the ball = -16(x² - 5x - 6), when the height of the ball is 0, which is when it is on the ground, we can set -16(x² - 5x - 6) equal to 0. This also allows us to divide by -16, and then we can solve the equation:
x² - 5x - 6 = 0
(x - 6)(x + 1) = 0
So x = 6 or x = -1, and because a quantity of time cannot be negative, x would have to be 6, which means it takes 6 seconds for the ball to reach 0 feet.
I hope this helps!