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Solve the system of equations y = 40x2 and y = 19x + 3 algebraically.

2 Answers

2 votes
Plug it in So you should get 19x+3=40x2 then solve for x
User Sint
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We have been given a system of nonlinear equations.


\\y=40x^(2),y=19x+3

In order to solve this system we can first equate the two equations in order to get a quadratic in x.


\\40x^(2)=19x+3

Our next step is to bring all the terms on one side.


\\40x^(2)-19x-3=0

Now we have to solve this equation. We can solve it by factoring using the splitting middle term method.


\\40x^(2)-24x+5x-3=0


\\8x(5x-3)+(5x-3)=0


\\(8x+1)(5x-3)=0

Upon setting each of these factors equal to zero using zero product property we get


\\8x+1=0 \text{ or } 5x-3 = 0

Upon solving both these equations we get


\\x=-(1)/(8) \text{ or } x=(3)/(5)

Now we can substitute these values of x in the equation


y=19x+3

We get


\text{For }x=- (1)/(8) \Rightarrow y=19(- (1)/(8))+3= (5)/(8)\\


\text{For }x= (3)/(5)\Rightarrow y=19( (3)/(5))+3= (72)/(5)\\

Therefore, our final set of solutions are


(x,y)=(- (1)/(8),(5)/(8)) \text{ and } ( (3)/(5), (72)/(5))


User Angel Yan
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