Question

What is the value of x in the equation x – y = 30, when y = 15?

4
8
80
200

Answer 1

There are many ways of solving the set of equations x + y = 30 and  x - y = 2 for x and y.

From x +y = 30 we get x = 30 - y

Now substitute this in the equation x - y = 2

30 - y - y = 2

-2y = -28

y = 14

As x = 30 - y = 30 - 14 = 16

The required solution of the set of equations is x = 16 and y = 14

Toodles~

Answer 2

Answer:

45

Step-by-step explanation:

We are given an equation x - y = 30 which we are to solve for x when the value of y is 15.

To solve this linear equation for x, we just need to substitute the given value of y into the equation to get the value of x.

x - y = 30

x - 15 = 30

x = 30 + 15

x = 45

Therefore, the value of x is 45 when y = 30.

Unfortunately this value is not in the given options but 45 is the correct answer.