Question

2x-4y=8 and 7x-3y=61 solve by substitution

Answer 1

2x= 8+4y. (Add 4y and move it to the other side)

X=8+4y/2 so X= 4+2y. (Divide both sides by 2)

Sub in 4+2y for x so 7(4+2y)-3y=61

Distribute: 28+ 14y -3y=61
Subtract 28 and add the y’s. 11y=33
Y=3

Answer 2

(10, 3)

Explanation:

Solve by Substitution

2x − 4y = 8 and 7x − 3y = 61

Solve for x in the first equation.

x = 4 + 2y 7x − 3y = 61

Replace all occurrences of x with 4 + 2y in each e quation.

Replace all occurrences of x in 7x − 3y = 61 with 4 + 2y. 7 (4 + 2y) − 3y = 61

x = 4 + 2y

Simplify 7 (4 + 2y) − 3y.

28 + 11y = 61

x = 4 + 2y

Solve for y in the first equation.

Move all terms not containing y to the right side of the equation.

11y = 33

x = 4 + 2y

Divide each term by 11 and simplify.

y = 3

x = 4 + 2y

Replace all occurrences of y with 3 in each equation.

Replace all occurrences of y in x = 4 + 2y with 3. x = 4 + 2 (3)

y = 3

Simplify 4 + 2 (3).

x = 10

y = 3

The solution to the system is the complete set of ordered pairs that are valid solutions.

(10, 3)

The result can be shown in multiple forms.

Point Form:

(10, 3)

Equation Form:

x = 10, y = 3