One number is 4 less than 3 times a second number. If 3 more than two times the first number is decreased by 2 times the second number, the result is 11. Use the substitution
method. What is the first number?

The first number (x) = 8

Step-by-step explanation:

Let x = the first number

Let y = the second number

x = 3*y - 4

2x + 3 - 2y = 11        Subtract 3 from both sides

2x - 2y = 11 - 3

2x - 2y = 8              Divide by 2

x - y = 4                   Add y to both sides

x = y + 4                  Now go back to the very first equation. Substitute for x

y + 4 = 3y - 4          Subtract y from both sides

4 = 3y - y - 4

4 = 2y - 4                Add 4 to both sides

4 + 4 = 2y

8 = 2y                     Divide by 2

8/2 = y

y = 4

x = 3y - 4

x = 3*4 - 4

x = 12 - 4

x = 8

a) 15/7

step-by-step explanation:

1/4 because there is 4 grades.