Y is partly constent and partly varries as the square of x.if y=40 when x=1 and y=13 when x =2.Find the expression for y in terms of x. Ii)the value of y when x=3

3 answers

y = a+bx^2
Now, solve
a+b = 40
a+4b = 13
and then you can find y when x=3.
How did you get the 4 in a + 4b = 13
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