Question

Please help me with this problem:)

Answer 1

Explanation:

`3x + y = 7 \: \: \: \: \: \: ...(1) \\ - 2x + y = - 3 \: \: \: \: \: \: \: ...(2)`

From (1) we get,

`x = (7 - y)/(3) \\`

put the value of x in equation 2

`- 2( (7-y)/(3) ) + y = - 3 \\ \\ - (14 -2y)/(3) + y = - 3 \\ \\ ( - 14 -2y+ 3y)/(3) = - 3 \\ \\ y - 14 = - 9 \\ y = + 14 - 9 \\ y = 5`

Now,

put the value of y in equation (1)

`3x + ( - 23) = 7 \\ 3x - 23 = 7 \\ 3x = 7 + 23 \\ 3x = 30 \\ \\ x = (30)/(3) \\ \\ x = 10`

Answer 2

(2,1)

Explanation:

3x+y = 7

-2x +y = -3

Solve the second equation for y by adding 2x to each side

-2x+2x +y = -3+2x

y = -3 +2x

Substitute into the first equation

3x+ (-3+2x) = 7

Combine like terms

5x -3 = 7

Add 3 to each side

5x-3+3 = 7+3

5x = 10

Divide by 5

5x/5 = 10/5

x=2

Now we need to solve for y

y = -3 +2x

y = -3 +2(2)

y = -3+4

y =1