Use substitution to solve y=4x+5 2x+y=17
Mathematics · High School · Thu Feb 04 2021
Answered on
Given the equation:
y = 4x + 5
2x + y = 17
Solve using substitution.
Solution:
In order to solve the equation using substitution, we simply needed to substitute the value of y from the first equation to the value of y for the 2nd equation.
2x + y = 17
2x + (4x + 5) = 17
Combine like terms and solve for x.
2x + (4x + 5) = 17
6x + 5 = 17
Trnaspose 5 to the other side of the equation, hence it must be taken to note that in transposing a number, the sign changes.
6x = 17 - 5
6x = 12
Divide both sides by 6 in order to determine the value of x.
6x/6 = 12/6
x = 2
Substitute the value of x to the first equation in order to determine the value of y.
y = 4x + 5
y = (4)(2) + 5
y = 8 + 5
y = 13
Final answer:
x = 2
y = 13