Find the solution to the equation below. 2x^2+3x-20=0
1 answer:
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.
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Step-by-step explanation:
ANSWER
The restrictions are
EXPLANATION
We were given the rational function,
The function is defined for all values of a, except
This has become a quadratic trinomial, so we need to split the middle term.
We do that by multiplying the coefficient of which is 5 by the constant term which is 3. This gives us 15.
The factors of 15 that adds up to 16 are 1 and 15.
We use these factors to split the middle term.
We now factor to get,
We factor further to get,
This implies that,
This gives
These are the restrictions.
Answer:
f(x) = 0.5x + 2
f(x) = 1/2x + 2
y - 3 = 1/2(x - 2)
y - 1 = 0.5(x + 2)
Step-by-step explanation:
In the figure attached, the graphed line is shown.
The missing options are:
<em>f(x) = 0.2x - 4 </em>
<em>f(x) = 0.5x + 2 </em>
<em> f(x) = 1/2x + 2 </em>
<em> y – 3 = 1/2(x – 2) </em>
<em> y – 1 = 0.5(x + 2)</em>
From the picture, we can see that points (0, 2) and (2, 3) are on the line. Then, the slope of the line is:
m = (3 - 2)/(2 - 0) = 1/2 = 0.5
The y-intercept is (0, 2), or b = 2
Therefore, in the slope y-intercept form, the equation is:
f(x) = mx + b
f(x) = 1/2x + 2 = 0.5x + 2
In the point-slope form, the equations is:
y - y1 = m(x - x1)
y - 3 = 1/2(x - 2)
Using point (-2, 1), in the point-slope form, the equation is:
y - y1 = m(x - x1)
y - 1 = 0.5(x + 2)
