solve the linear expressions and show all work by using subs

solve the linear expressions and show all work by using substitution, 2x-3y=-7 and 3x+7y=24 and 7.2x-4.1y=7.0 and -3.5x+16.5y=2.4

1) 2x-3y=-7 and 3x+7y=24

Multiply each equation by a number that will create opposite coefficients for x.

In this case we will multiply first equation by -3 and the second equation by 2.

After multiplying we have the following system:

6x+9y = 21

6x+14y = 48

add the two equations together to eliminate x from the system.

23y=69 ----> y =3

2x3(3)=7

x = 1

2) 7.2x-4.1y=7.0 and -3.5x+16.5y=2.4

Get rid of the decimals .by multiplying first equation by 10 and second equation by 10.

After multiplying we have the following system:

72x41y=70

35x+165y =24

Multiply each equation by a number that will create opposite coefficients for x.

In this case we will multiply first equation by 35 and the second equation by 72.

After multiplying we have the following system:

2520x1435y=2450

2520x+11880y=1728

------------------------( subtract)

y = 2/5 = 0.4

on substitution value of y we get value of x= 6/5 = 1.2