Answer:
x = -4, 5/2
Step-by-step explanation:
A quadratic can be solved may ways, including graphing, factoring, and the quadratic formula. You can also check possible answers by making use of the relationships between solutions and the coefficients.
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A graph is attached. It shows the solutions to be -4 and 5/2.
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When factored, the equation becomes ...
(2x -5)(x +4) = 0 . . . . . has solutions x=-4, x=5/2 (these make the factors zero)
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Using the quadratic formula, the solutions of ax^2 +bx +c = 0 are found from ...
x = (-b±√(b²-4ac))/(2a)
x = (-3±√(3²-4(2)(-20))/(2(2)) = (-3±√169)/4 = {-16, +10}/4
x = {-4, 5/2}
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For ax^2 +bx +c = 0, the solutions must satisfy ...
product of solutions is c/a = -20/2 = -10
Only the first and last choices have this product.
sum of solutions is -b/a = -3/2
Only the first choice (-4, 5/2) has this sum.
Answer: Tiffany 15mph, Maggie 20mph
Step-by-step explanation:
Set up the equation 4((x+5) + x) = 140. x+5 represents how many miles Maggie covered in one hour. x represents how much Tiffany traveled in one hour. 140 is the number of miles in total. 4 is the number of hours in total.
Simplify the equation.
(x+5) + x = 35 Divide both sides by 4
2x+5 = 35 Combine like terms
2x = 30 Subtract 5 from both sides
x = 15 Divide both sides by 2
Tiffany traveled 15mph, while Maggie traveled 15+5=20mph.
Answer:
In the second step, the +16 should be -16
In the 3rd step, you should add 16 instead of subtracting 16
m=0
108 i really hope this help :)