Answer:
x = ± 
i
Step-by-step explanation:
subtract 64 from both sides
9x² = - 64 ( divide both sides by 9 )
x² = - 
( take the square root of both sides )
x = ± 
= ± i
Answer:
3686
Step-by-step explanation:
35.4% expressed as a decimal is .354
*Anchor: if you got 100% on your test, you got 1 whole test right.
Notice how I moved the decimal back two places to change 100% to 1
*An anchor is something that helps you remember what to do in the future. Use the anchor above to help you remember which way to move the decimal point when you change a percent to a decimal.
Answer: y = -14/9(x + 4)^2 + 7
Step-by-step explanation:
The given roots of the quadratic function is (-1, -7)
The vertex is at (-4, 7)
The formula is
y = a(x - h)^2 + k
The vertex is (h, k)
Comparing with the given vertex, (-4, 7), h = -4 and k = 7
Substituting into the formula
y = a(x - h)^2 + k, it becomes
y = a(x - - 4)^2 + 7
y = a(x + 4)^2 + 7
From the roots given (-1, -7)
x = -1 and y = -7
Substituting x = -1 and y = -7 into the equation,
y = a(x + 4)^2 + 7, it becomes
-7 = a(-1+4)^2 + 7
-7 = a(3^2 ) + 7
- 7 = 9a + 7
-7-7 = 9a
9a = -14
a = -14/9
Substituting a = - 14/9 into the equation, it becomes
y = -14/9(x + 4)^2 + 7
If y=8-x then you can plug that into the equation like 7=2-(8-x). When you distribute the equation becomes 7=2-8+x. Once you combine like terms the equation becomes 7=-6+x. Then you subtract 6 from both sides, which gives you 13=x.
To find y just put 13 where x was in the first equation. Y=8-13.
Y=-5
X=13
