Solve the system of equations by graphing.
x+y=-7
4x+y=19

See attachment below

Step-by-step explanation:

Consider the given system of equation

x + y = -7     ........(1)

4x + y = 19   ..........(2)

Consider the equation (1)

x + y = -7

We first find different values of x and y that satisfies (1),

1) x = 1 , y = -7-1 = -8  

We get one point as (1,-8)

2) x= 2 , y = -7 -2 = -9

We get  point as (2 ,-9)

3) x = 0 , y = -7

We get point as (0 ,-7)

Similarly, find different values of x and y that satisfies (2),

4x + y = 19  

1) x = 2 , y = 19 -  8 = 11

We get  point as (0,11)

2)  x= 3 , y = 19 - 12 = 7

We get  point as (3 , 7)

3) x= 4 , y = 19 - 16 = 3

We get  point as (4 ,3)

Now , we plot these point on the graph paper,  we obtained graph as, (as attached below)

grace would use 12 apple slices