Answer:
2y = 3x + 21
y = 1.5x + 10.5
plug in, in the second equation
- 4x + (1.5x + 10.5) = 23
-4x + 1.5x + 10.5 = 23
-2.5x + 10.5 = 23
-2.5x = 12.5
x = 12.5/-2.5 = -5
y = 1.5 (-5) + 10.5 = 3
x = -5
y = 3
Answer: x=-5 and y=3
Step-by-step explanation:
-3x + 2y = 21 ............ Eq 1
-4x + y = 23 .............. Eq2
In eq 2,let's make y the subject of the formula ; add 4x to both sides to get : - 4x + 4x + y = 23 + 4x
Which gives: y = 23 + 4x .... Eq3
Put this value of y into eq 1 to get;
-3x + 2(23 + 4x) = 21
Which gives: - 3x + 46 + 8x = 21
Which givea; 5x + 46 = 21
Subtract 46 from both sides to get;
5x + 46 - 46 = 21 - 46 to get
5x = - 25
Divide both sides by 5;
5x/5 = - 25/5
Therefore, x = - 5
Now,put - 5 for x in Eq3;
y = 23 + 4(-5)
y = 23 - 20
y = 3
Therefore the solution to the question is x=-5 and y=3
