Question

Consider the following system of equations:

2x + 3y = 45
x+y = 10
What is the x-value of the solution for this system?
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Answer 1

Explanation:

Using substitution method of simultaneous equation,

2x + 3y = 45 ___________(1)

x + y = 10 ___________(2)

From equation 2 solve for x to produce equation 3

x = 10 - y ______________(3)

Now put equation 3 or rather substitute for x in equation 1

2( 10 - y )+ 3y = 45

Solve the equation now

2x10 -2 X y + 3y =45

20 -2y +3y = 45

y = 45 - 20

y = 25

To get x, substitute for y in equation 3

x = 10 - 25

x = -15

Therefore,

x = -15.

,To check.

Put x=-15 and y = 25 in equation

x +y = 10

-15 +25 = 10.

Therefore, x = -15.

Answer 2

x=-15, y=25. (-15, 25).

Explanation:

2x+3y=45

x+y=10

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x=10-y

2(10-y)+3y=45

20-2y+3y=45

20+y=45

y=45-20

y=25

x+25=10

x=10-25

x=-15