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NO LINKS!! Use the method of to solve the system. (if there's no solution, enter no solution). Part 2z​

NO LINKS!! Use the method of to solve the system. (if there's no solution, enter no-example-1
User DCurro
by
3.1k points

2 Answers

29 votes
29 votes

Answer:

smaller x-value: (-4, 18)

larger x-value: (3, 11)

Explanation:

Solving for x:

y = x^2 + 2

x + y = 14 ---> y = 14 - x

14 - x = x^2 + 2

0 = x^2 + x - 12

0 = (x + 4)(x - 3)

x = -4 or 3

Solving for y:

If x = -4

y = 14 + 4

y = 18

if x = 3

y = 14 - 3

y = 11

User Pqnet
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3.0k points
19 votes
19 votes

Answer:


(x,y)=\left(\; \boxed{-4,18} \; \right)\quad \textsf{(smaller $x$-value)}


(x,y)=\left(\; \boxed{3,11} \; \right)\quad \textsf{(larger $x$-value)}

Explanation:

Given system of equations:


\begin{cases}\phantom{bbbb}y=x^2+2\\x+y=14\end{cases}

To solve by the method of substitution, rearrange the second equation to make y the subject:


\implies y=14-x

Substitute the found expression for y into the first equation and rearrange so that the equation equals zero:


\begin{aligned}y=14-x \implies 14-x&=x^2+2\\x^2+2&=14-x\\x^2+2+x&=14\\x^2+x-12&=0\end{aligned}

Factor the quadratic:


\begin{aligned}x^2+x-12&=0\\x^2+4x-3x-12&=0\\x(x+4)-3(x+4)&=0\\(x-3)(x+4)&=0\end{aligned}

Apply the zero-product property and solve for x:


\implies x-3=0 \implies x=3


\implies x+4=0 \implies x=-4

Substitute the found values of x into the second equation and solve for y:


\begin{aligned}x=3 \implies 3+y&=14\\y&=14-3\\y&=11\end{aligned}


\begin{aligned}x=-4 \implies -4+y&=14\\y&=14+4\\y&=18\end{aligned}

Therefore, the solutions are:


(x,y)=\left(\; \boxed{-4,18} \; \right)\quad \textsf{(smaller $x$-value)}


(x,y)=\left(\; \boxed{3,11} \; \right)\quad \textsf{(larger $x$-value)}

User Raphael Ayres
by
2.7k points