Answer:
y = (x - 4)² - 25
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
To obtain this form use the method of completing the square.
Given
y = (x + 1)(x - 9) ← expand factors using FOIL, thus
y = x² - 8x - 9
To complete the square
add/subtract ( half the coefficient of the x- term )² to x² - 8x
y = x² + 2(- 4)x + 16 - 16 - 9
= (x - 4)² - 25 ← in vertex form
complementary angles add up to 90°, so therefore we know that ∡A + ∡B = 90°, and also they are in a ratio of 3:6.
![\bf \cfrac{A}{B}=\cfrac{3}{6}\implies \cfrac{A}{B}=\cfrac{1}{2}\implies 2A=\boxed{B} \\\\[-0.35em] ~\dotfill\\\\ A+B=90\implies A+\boxed{2A}=90\implies 3A=90\\\\\\ A=\cfrac{90}{3}\implies \blacktriangleright A=30 \blacktriangleleft \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ 2(30)=B\implies \blacktriangleright 60=B \blacktriangleleft](https://tex.z-dn.net/?f=%5Cbf%20%5Ccfrac%7BA%7D%7BB%7D%3D%5Ccfrac%7B3%7D%7B6%7D%5Cimplies%20%5Ccfrac%7BA%7D%7BB%7D%3D%5Ccfrac%7B1%7D%7B2%7D%5Cimplies%202A%3D%5Cboxed%7BB%7D%0A%5C%5C%5C%5C%5B-0.35em%5D%0A~%5Cdotfill%5C%5C%5C%5C%0AA%2BB%3D90%5Cimplies%20A%2B%5Cboxed%7B2A%7D%3D90%5Cimplies%203A%3D90%5C%5C%5C%5C%5C%5C%20A%3D%5Ccfrac%7B90%7D%7B3%7D%5Cimplies%20%5Cblacktriangleright%20A%3D30%20%5Cblacktriangleleft%0A%5C%5C%5C%5C%5B-0.35em%5D%0A%5Crule%7B34em%7D%7B0.25pt%7D%5C%5C%5C%5C%0A2%2830%29%3DB%5Cimplies%20%5Cblacktriangleright%2060%3DB%20%5Cblacktriangleleft)
The answer is 27.1052631579 or 27.1 if you rounded "m" to .10
650-15%= 552.50 (they pay the manager 97.50) which leaves 552.50 profit 10% goes to ST(55.25 to the ST) which is 497.25 left for the band
