Solve the system by substitution.

3x-7y=12
3x-12y=6

x=34/5 y=6/5

Step-by-step explanation:

so first you need to isolate one variable in one equation

so lets use 3x-12y=6

3x=12y+6

x=4y+2

then, as the name implies, we substitute it into the second equation

3(4y+2)-7y=12

then we simplify

12y+6-7y=12

5y=6

y=6/5

then we plug it in to find x

3x-7(6/5)=12

3x-42/5=12

3x=102/5

x=34/5

check work

3(34/5)-12(6/5)=6

102/5-72/5=6

30/5=6

6=6

3< x< 5

step-by-step explanation:

|x - 4| < 1

there are two solutions, one positive and one negative.   remember to flip the inequality when taking the negative solution

x-4 < 1       x-4 > -1

add 4 to each side

x-4+4 < 1+4       x-4+4 > -1+4

x< 5                 x> 3

3< x< 5

first, we define the variables:

x: number of years after 1950

f (x): amount of vinyl sold.

then, with the variables defined, we have:

68594 vinyl records were sold in 1958 > f (8) = 68594

91299 vinyl records were sold in 1961 > f (11) = 91299

38720 vinyl records were sold in 1952 > f (2) = 38720

161743 vinyl records were sold in 1967 > f (17) = 161743

read more on -

step-by-step explanation: