Answer:
(2,16)
Step-by-step explanation:
y=-x+18
y=8x
8x=-x+18
8x+x=9x
-x+x=0
9x=18
9x/9=x
18/9=2
x=2
y=8(2)
y=16
Answer: x = 1.5
Step-by-step explanation:
5x - 2 = x + 4
Add 2 to each side
5x = x + 6
Subtract x from each side
4x = 6
Divide each side by 4
x = 1.5
Answer:
2 inches
Step-by-step explanation:
Since his actual height was 4 feet and 2 inches, instead of the estimate of 4 feet, the difference was 2 inches.
This means the error in inches was also 2 inches, since the estimated height was 2 inches lower than the one at the doctor's office.
So, the error is 2 inches
B. Is the correct answer. For part B, he can buy 15 balloons since X=15. Plug this back into the equation to check: 2(15)+20=50.
2(15)=30+20=50.
Answer: True
Solution:
Rearrange the equation to the LHS:
[x^2 + 8x + 16] · [x^2 – 8x + 16] - (x^2 – 16)^2 = 0
Factoring x^2+8x+16
x^2 - 4x - 4x - 16
= (x-4) • (x-4)
= = (x+4)2
So now we have an equation
(x + 4)^2 • (x - 4)^2 - (x^2 - 16)^2 = 0
Step 2: Evaluate the following:
(x+4)2 = x^2+8x+16
(x-4)2 = x^2-8x+16
(x^2-16)2 = x^4-32x^2+256
(x^2+8x+16) (x^2-8x+16 ) - (x^4-32x^2+256 )
0 = 0
Hence True
