can you help me solve this?

0 ⤊

can you help me solve this?

y = -x² + 8x - 20

and if possible, reduce it...

2007-12-05 11:08:49 · 2 answers · asked by Juan C 6 in Science & Mathematics ➔ Mathematics

2 answers

y = - x² + 8x - 20
y = - (x² - 8x + 20)
y = - (x² - 8x + 16 - 16 + 20)
y = - ((x - 4)² + 4) = - (x - 4)² - 4 (vertex form)
y = - (x - 4 + i2)(x - 4 - i2)

2007-12-05 11:29:12 · answer #1 · answered by Helmut 7 · 0⤊ 0⤋

-x^2+8x-20
consider ax^2+bx+c=0
a=-1 b=8 c=-20
x=[-b+/-sqrt(b^2-4ac)]/2a
b^2-4ac=8^2-4(-1)(-20)
=64-80=-16 < 0
This expression cannot be factored.

2007-12-05 19:22:43 · answer #2 · answered by cidyah 7 · 0⤊ 0⤋