solve the equations
2006-12-07 13:27:10 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
y^2-8y=0
0 = 8^2-8(8) = 64 - 64 = 0
y = 8
14y^2+70y=0
0 = 14(-5^2) + 70(-5) = 14(25) + -350 = 350 - 350 = 0
y = -5
13x^2=-65x
13(-5 ^ 2) = -65(-5)
13(25) = 325
325 = 325
x = -5
2006-12-07 13:36:38 · answer #1 · answered by ? 2 · 0⤊ 0⤋
y² - 8y = 0 --- Factor out "y"...
(y)(y - 8) = 0 --- Either y = 0 or (y - 8) = 0...
y - 8 = 0 --- Add 8 to both sides...
y = 8
ANSWER: y = 8 or y = 0
CHECK:
y = 0
(0)² - 8(0) = 0
0 - 0 = 0
0 = 0 --- y = 0 checks out...
y = 8
(8)² - (8)(8) = 0
64 - 64 = 0
0 = 0 --- y = 8 checks out...
14y² + 70y = 0 --- Factor out 14y...
(14y)(y + 5) = 0 --- Either 14y = 0 or (y + 5) = 0...
14y = 0 --- Divide both sides by 14...
y = 0
y + 5 = 0 --- Subtract 5 from each side...
y = -5
ANSWER: y = 0 or y = -5
CHECK:
y = 0
14(0²) + 70(0) = 0
0 + 0 = 0
0 = 0 --- y = 0 checks out...
y = -5
14(-5²) + 70(-5) = 0
14(25) + 70(-5) = 0
350 - 350 = 0
0 = 0 --- y = -5 checks out...
13x² = -65x --- Add 65x to both sides...
13x² + 65x = 0 --- Factor out 13x...
13x(x + 5) = 0 --- Either 13x = 0 or x + 5 = 0
13x = 0 --- Divide both sides by 13...
x = 0
x + 5 = 0 --- Subtract 5 from both sides...
x = -5
ANSWER: x = 0 or x = -5
CHECK:
x = 0
13(0²) = -65(0)
0 = 0 --- x = 0 checks out...
x = -5
13(-5²) = -65(-5)
13(25) = -65(-5)
325 = 325 --- x = -5 checks out...
FINAL ANSWER:
1) y = {0; 8}
2) y = {0, -5}
3) x = {0, -5)
2006-12-07 13:53:54 · answer #2 · answered by Anonymous · 0⤊ 0⤋
one million)y^2 + 8y = 0 y(y+8)=0 Now: y = 0 or y = -8 2) x^2 + 3x -28 = 0 you may finished the sq.: x2 + 3x = 28 Now look on the term in front of the x.. you halve that and sq. it and upload it to the two facets. (one million/2)*3 = 3/2 (3/2)^2 = 9/4 x^2 + 3x + 9/4 = 112/4 +9/4 Now as you will discover the 9/4 cancels out, meaning we've not replaced the unique equation in any respect! yet we don't cancel out the 9/4 right here. We simplifiy the suitable area: x^2 + 3x + 9/4 = 121/4 Now: x^2+3x+9/4 = (x+3/2)^2 --> because of the fact we finished the sq.: (x+3/2)^2 = 121/4 x+3/2 = sqrt(121/4) x+3/2 = +/- 11/2 x = +/- 11/2 -3/2 So: x = -14/2 = -7 or x = 8/2 = 4
2016-12-13 04:54:03 · answer #3 · answered by Anonymous · 0⤊ 0⤋
I would agree with Crazy Horse and that's how you would solve the variable...hope ya understand Crazy Horse's solving processes...if not...feel free ask me any questions...I'm in Calculus AP
2006-12-07 14:07:37 · answer #4 · answered by Awesome Auzy 2 · 0⤊ 0⤋
DO YOUR OWN HOMEWORK.
2006-12-07 13:36:19 · answer #5 · answered by kittenpie 3 · 0⤊ 0⤋
did aliens made these up?^^^^^^? :P
2006-12-07 13:29:37 · answer #6 · answered by Anonymous · 0⤊ 0⤋