solve 2x+3y=11 and 2x-4y=-24y and hence find the value of m for which y=mx+3
Answers
The value of m is
Step-by-step explanation:
- Given data
2 x -4 y = -24 y ...1)
2 x = -24 y + 4 y
2 x = - 20 y
x = - 10 y ... 2)
- Now come to second equation
2 x + 3 y = 11 (Put value x in term of y)
2 (-10 y) + 3 y = 11
-20 y + 3 y = 11
-17 y = 11
So
...3)
- Then
...4)
- Now come to equation
y = m x + 3 ( put value of x and y)
2x + 3y = 11…………………………..(i)
2x + 3y = 11…………………………..(i)2x – 4y = -24………………………… (ii)
From equation (ii), we get;
x = (11 – 3y)/2 ……….…………………………..(iii)
Putting the value of x in equation (ii), we get
2[(11 – 3y)/2] – 4y = −24
11 – 3y – 4y = -24
-7y = -35
y = 5……………………………………..(iv)
Putting the value of y in equation (iii), we get;
x = (11 – 15)/2 = -4/2 = −2
Hence, x = -2, y = 5
Also,
y = mx + 3
5 = -2m +3
-2m = 2
m = -1