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.
__
A graph is attached. It shows the solutions to be -4 and 5/2.
__
When factored, the equation becomes ...
(2x -5)(x +4) = 0 . . . . . has solutions x=-4, x=5/2 (these make the factors zero)
__
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}
__
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.
Answers:
- x = 4
- AB = 36
- BC = 36
- AC = 36
All three sides are 36 units long.
===========================================================
Explanation:
Triangle ABC is equilateral, so all three sides are the same length.
Pick any two of those sides, set them equal to each other, and solve for x
AB = BC
8x+4 = 11x-8
8x-11x = -8-4
-3x = -12
x = -12/(-3)
x = 4
Use this x value to find each side. We should get the same value (if not, then an error occurred in solving for x).
- AB = 8x+4 = 8*4+4 = 32+4 = 36
- BC = 11x-8 = 11*4-8 = 44-8 = 36
- AC = 9x = 9*4 = 36
We get the same value for the three side lengths, so this confirms we have the correct x value.
Answer:
C
Step-by-step explanation:
g is distributed
You are X, if your friend is 1.2 times taller than you= 1.2X
That's why 64.5=1.2X
X=53.75
But you should write 53.8 inches tall. Because there is one number after point.
<span>As a result, you are 53.8 inches tall
</span>
20 and 28 can be divided by 4, so just take the 4 out so the answer should be 4(5x - 7)
