4x+5y=27
x=26-4y
4(26-4y) + 5y = 27
104 - 16y+ 5y = 27
-21y = - 77
21y = 77
y = 77/31
Now, I’m suppose to return to the 2nd equation x=26-4y and substitute 77/31 for x, I don’t understand if the is correct way or how to get the answer for the ordered pair.
-16y+5y=-11y, not -21y..I think that's your mistake
the answer is x= -2 and y= 7, this is how its done
4(26-4y)+5= 27
104-16y+5y=27
104-11y=27
-11y=-77
y= 7
then you plug in the y for the next equation
4x+5(7)=27
4x+35=27
4x=-8
x=-2
and that's how you get your x and y i hope that helped
Ok, so if I use the corrected number you gave, that would make y = 7.
Returning to the 2nd equation x=26-4y and substituting x for 7.
4y = 7 - 26
still does not add up, what am I doing wrong?
Ana, thank you, now I understand what I was doing wrong. I couldn't figure out how to rewrite the x=26-4y equation.
To find the ordered pair (x, y), you need to substitute the value of y (= 77/31) into the equation x = 26 - 4y. Let's do it step by step:
Given equations:
1) 4x + 5y = 27
2) x = 26 - 4y
Substitute the value of y into equation 2:
x = 26 - 4(77/31)
x = 26 - 308/31
x = (26 * 31 - 308) / 31
x = (806 - 308) / 31
x = 498 / 31
x = 16
Therefore, the ordered pair (x, y) is (16, 77/31).