Answer:
Step-by-step explanation:
<u>Sum of (7x+4) and the opposite of 7x:</u>
- 7x + 4 + (-7x) =
- 7x + 4 - 7x =
- 4
Answer:
x intercept: (3, 0), (7, 0)
y-intercept: (0, -21)
vertex : (5,4)
the graph points down
Step-by-step explanation:
f(x) = - (x - 3)(x - 7)
f(x) = - (x^2 - 7x - 3x + 21)
f(x) = - (x^2 - 10x + 21)
f(x) = -x^2 + 10x - 21
x-intercept when f(x) = 0 so
x - 3 = 0; x = 3
x - 7 = 0; x = 7
x intercept: (3, 0), (7, 0)
y-intercept when x = 0 so y = -21
y-intercept: (0, -21)
vertex:
x = -b/2a
x = -10/ 2(-1)
x = 5
plug in x = 5 into the equation to find y
y = -(5)^2 + 10(5) - 21
y = -25 + 50 - 21
y = 4
so vertex : (5,4)
Since a = - 1<0, the graph is going downward and has maximum
Your answer will be 70x^2 -138x+56
Third option is the correct answer.
Answer:
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Step-by-step explanation:
![y - y_1 = m(x - x_1) \\ \\ y - 0 = \bigg[ \frac{2b}{(2a - c)} \bigg] (x - c) \\ \\ y = \bigg[ \frac{2b}{(2a - c)} \bigg]x - \bigg[ \frac{2b}{(2a - c)} \bigg]c \\ \\ \purple { \boxed{ \bold{y = \bigg[ \frac{2b}{(2a - c)} \bigg]x - \bigg[ \frac{2bc}{(2a - c)} \bigg]}}} \\](https://tex.z-dn.net/?f=y%20-%20y_1%20%3D%20m%28x%20-%20x_1%29%20%5C%5C%20%20%5C%5C%20y%20-%200%20%3D%20%20%20%5Cbigg%5B%20%5Cfrac%7B2b%7D%7B%282a%20-%20c%29%7D%20%5Cbigg%5D%20%20%28x%20-%20c%29%20%5C%5C%20%20%5C%5C%20y%20%3D%20%5Cbigg%5B%20%5Cfrac%7B2b%7D%7B%282a%20-%20c%29%7D%20%5Cbigg%5Dx%20-%20%5Cbigg%5B%20%5Cfrac%7B2b%7D%7B%282a%20-%20c%29%7D%20%5Cbigg%5Dc%20%5C%5C%20%20%5C%5C%20%20%5Cpurple%20%7B%20%5Cboxed%7B%20%5Cbold%7By%20%3D%20%5Cbigg%5B%20%5Cfrac%7B2b%7D%7B%282a%20-%20c%29%7D%20%5Cbigg%5Dx%20-%20%5Cbigg%5B%20%5Cfrac%7B2bc%7D%7B%282a%20-%20c%29%7D%20%5Cbigg%5D%7D%7D%7D%20%5C%5C%20)
