Question

Challenge question: Solve for 7 and check.-a + 7 = 11

Answer 1

This problem is about a linear equation, where its variable is a.

First, we need to subtract each side of the equation by 7-

`-a+7-7=11-7`
`-a=4`

Now, we need to multiply the equation by -1, to have the variable positive

`-a(-1)=4(-1)`
`a=-4`

Once we have the value of the variable, we can check if the answer is right. To do that, we just need to substitute this value in the given equation.

`-a+7=11`
`-(-4)+7=11`
`4+7=11\text{ }\rightarrow\text{ 11=11}`

As you can observe, the answer satisfies the equation.

Therefore, the right answer is -4.