x = a + by
you are given that
19 = a + 5b
34 = a + 10b
So, solve for a and b, and then plug in y=7
if x is partly constant and partly varies with y when y=5,x=19 and when y=10,x=34.
find the relationship between x and y.
find x when y=7
5 answers
I want an answer
Yes
x=a+by
19=a+5b -----(i)
34=a+10b -----(ii)
Multiply equation (i) by 2
38=2a+10b---(iii)
Subtract equation (ii) from (iii)
38=2a+10b
34=a+10b
38-34=2a-a
4=a
:
19=a+5b -----(i)
34=a+10b -----(ii)
Multiply equation (i) by 2
38=2a+10b---(iii)
Subtract equation (ii) from (iii)
38=2a+10b
34=a+10b
38-34=2a-a
4=a
:
substitute a=4 into equation (i)
19=4+5b
15=5b
b=3
a=4 and b=3
Relationship between x and y is
x=4+3y
When y =7,
x=a+by
x=4+3×7
x=4+21
x=25
19=4+5b
15=5b
b=3
a=4 and b=3
Relationship between x and y is
x=4+3y
When y =7,
x=a+by
x=4+3×7
x=4+21
x=25
5 answers