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3 votes
Solve using elimination

2x+5y=-23
5x+13y=-60

User Grofit
by
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2 Answers

6 votes

Answer:

Point Form: (1,-5)

Equation Form: x-1,y=-5

Explanation:

Add the equation in order to solve for the first variable. Plug this value into the other equations in order to solve for the remaining variables.

User Noctonura
by
5.6k points
4 votes

Answer:

x = 1

y = -5

Explanation:

This is a simultaneous equation question.

We are given two equations and we shall label the equations as equation 1 and 2.

2x + 5y = -23...... (i)

5x + 13y = -60......(ii)

Step one

First step to solving simultaneous equations by elimination method is to ensure one of the terms that has an unknown, (in this case, either x or y) is the equal in the two equations.

To do this, we multiply equation one by 5 and equation two by 2

5 x (i) = 10x + 25y = -115.... (iii)

2 x (ii) = 10x + 26y = -120....(iv)

To eliminate the term that has x, we subtract equation (iii) from equation (iv)

(iv) - (iii) =

(10x - 10x) + (26y - 25y) = -120 - (-115)

y = -5

We substitute the new value of y = -5 into equation (i)

2x + 5y = -23

2x + 5(-5) = -23

2x - 25 = -23

We collect like terms by adding 25 to both sides of the equation

2x - 25 + 25 = -23 + 25

2x = 2

We divide both sides of the equation by the coefficient of x to find the value of x. The coefficient of x is 2

2x/2 = 2/2

x = 1

Therefore, the solutions to the simultaneous equations using elimination method are

x = 1 and y = -5

User Sisyphe
by
4.6k points