Answer:
The x-intercepts will be, x= 7 or x =9
Step-by-step explanation:
f(x)= x^2 -16x+63
At the x-intercept, f(x) is zero.
Therefore;
x² - 16x + 63 = 0
solving it quadratically;
product = 63
Sum = -16
x² - 9x - 7x + 63 = 0
x(x-9) - 7( x-9) = 0
(x-7) (x-9) = 0
x = 7 or x = 9
Therefore;
The x-intercepts will be, x= 7 or x =9
Its a simultaneous equation:
lets make "x" the used games and "y" the new ones
4x + 2y = 84
6x + y = 78. (multiply this by 2 to cancel out y)
12x + 2y = 156
so now we subtract them:
12x - 4x = 156 - 84
x = 9
used games cost $9
new games cost 78 - 6(9) = $24
Janet has $120 but she already bought 3 NEW games so:
120 - 3(24) = $48 left
48/9 = how many used ones she can buy = 5. something
she can buy 5 used
The formula to find the midpoint of a segment is ((x1 + x2)/2,),(y1 + y2)/2).
The x coordinate of the first point is -4, and the x coordinate of the second point is -8. The y coordinate of the first point is 6, and the y coordinate of the second point is -2. Now, we can plug these into our formula.
((-4 + (-8))/2), (6 + (-2))/2)) = (-12/2), (4/2) = (-6, 2)
So, (-6, 2) is the midpoint of the segment.