2007-01-17 09:11:39 · 2 answers · asked by brunettebelle10 2 in Education & Reference ➔ Primary & Secondary Education
Basic quadratic function ax^2+bx+c
Decompose the function by finding factors of AC that add together to equal b.
Therefore factors of -70 that add together to equal -9. one of the factors of 70 is 14 and 5. Therefore -14 and +5 added together equal -9.
Write the deomposed function
2x^2 -14x +5x-35 =0
take common factors of each half of the function
2x(x-7) +5(x-7) =0
(2x+5)(x-7)=0
therefore 2x+5 = 0 or x-7 = 0
x=-2 1/2 or x=7
2007-01-17 09:38:42 · answer #1 · answered by roger h 1 · 0⤊ 0⤋
The answer is X = 5/2 and 7. The only work I know how to show is this: starts with 2x^2 - 9x - 35 = 0 factor it down to (2x + 5)(x - 7), then set 2x + 5 = 0 and solve for x which is the 5/2 answer and set x - 7 = 0 and solve for x which is 7. sorry if I didnt explain it good enough but that the best I can do.
2007-01-17 09:42:57 · answer #2 · answered by Sleeves 3 · 0⤊ 0⤋