186k views
12 votes
-3x+4y=7 y=3x-5 I NEED HELP PL Z HELP ME

1 Answer

4 votes


- 3x + 4y = 7 \\ y = 3x - 5

  • [Substitute the given value of y into the first equation]


- 3x + 4 * (3x - 5) = 7

  • [Distribute 4 through the parentheses]


- 3x + 12x - 20 = 7

  • [Collect like terms]


9x - 20 = 7

  • [Move the constant to the right-hand side and change its sign]


9x = 7 + 20

  • [Add the numbers]


9x = 27

  • [Divide both sides of the equation by 9]


x = 3

  • [Substitute the given value of x into the second equation]


y = 3 * 3 - 5

  • [Multiply the numbers]


y = 9 - 5

  • [Subtract the numbers]


y = 4

  • [The possible solution of the system is the ordered pair (x,y)]


(x,y)=(3,4)