7d-9=54

Cat1864

What part of the equation are you having problems with?

Can you show me what you have done so far?

HAMAYUN

nothin i have done nothing

Cat1864

I can't give you any help if I don't know where you are having problems and what you have tried to do.

Perito

If you add something to both sides of the equality, you will still have an equality. For example, here is a trivial equality

8=8

--------------------------------------- addition/subtraction

If you add 3 to both sides of the equality, you'll still have an equality

8+3=8+3
or
11=11

In your case, you have

7d-9=54

Try adding 9 to both sides of the equation to see what happens. The goal is to isolate the "d" (possibly along with a multiplier or divisor) on one side of the equal sign.

--------------------------------------- multiplication/division

If you have an equality and multiply or divide both sides of the equality by a value, you'll still have an equality. For example

8=8

Divide both sides of the equality by 4


or
2=2

Try figuring out what to divide both sides by so the coefficient of "d" is 1 (the coefficient is the multiplier).

HAMAYUN

we have to do the opposite like its - sign so we have to change it to addition right

Perito

Yes. But remember that addition and subtraction are really the same thing -- with reversed signs. You can add a negative number. That's the same as subtracting a positive number.

Unknown008

It's also time that you start to understand how to solve these kinds of numbers. That makes one month since you started to ask about how to solve equations involving a single variable. You posted about 7 different questions, and I must say, this one question was not the most difficult of them, which therefore you could have done using the other answers you got for the other questions you asked, that is using the same principle.