The value of (x-y) is 16
Further explanation:
We have to use the given values to find the value
Given

We will use:

Simplifying by using: 
So,

As we know that x+y=4
Putting the value in equation

Dividing both sides by 4

The value of (x-y) is 16
Keywords: Algebraic formulas, Simplification
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Answer:
10/81
Step-by-step explanation:
let,
y=kx
y=10 when x=9
so,
10=k×9
or, k=10/9
when x=1/9
y=kx
or, y=(10/9)×(1/9)
or, y=10/81
50% means half so divide 170 by 2,
170/2=85
so there is 85 boys
Hope this helped!!
6 / 2 = 3
21 / 7 = 3
Yes, 2/7 and 6/21 are equivalent ratios. The second number is simply the first number tripled.