Question.
Solve $2 x+3 y=11$ and $2 x-4 y=-24$ and hence tind the value of ' $m$ ' for which $y$ $=m x+3$
Solve $2 x+3 y=11$ and $2 x-4 y=-24$ and hence tind the value of ' $m$ ' for which $y$ $=m x+3$
Solution:
2x + 3y = 11 ......(i)
2x – 4y = –24 ......(ii)
Subtract equation (ii) from (i), we get
2x + 3y – 2x + 4y = 11 + 24
7y = 35
y = 5
Substituting value of y in equation (i), we get
2x + 3 × 5 = 11
2x = 11 – 15
$x=-\frac{4}{2}=-2$
Now, x = –2, y = 5
Puting value of x & y in y = mx + 3
5 = –2m + 3
2 = –2m
m = –1
2x + 3y = 11 ......(i)
2x – 4y = –24 ......(ii)
Subtract equation (ii) from (i), we get
2x + 3y – 2x + 4y = 11 + 24
7y = 35
y = 5
Substituting value of y in equation (i), we get
2x + 3 × 5 = 11
2x = 11 – 15
$x=-\frac{4}{2}=-2$
Now, x = –2, y = 5
Puting value of x & y in y = mx + 3
5 = –2m + 3
2 = –2m
m = –1