[Click to learn about the “ What? Why? How?" strategy]

To use this strategy, ask yourself these
“
What? Why? How?"
questions while solving a problem.

What are you doing or thinking right now?

Why is what you are currently doing helpful? Why is it useful for achieving your goal?

How well is your current approach to this problem working?

As a reminder to ask yourself these questions, they will sometimes appear in purple.

What if I can’t do it?

What are you doing or thinking right now?

Why is what you are currently doing helpful? Why is it useful for achieving your goal?

How well is your current approach to this problem working?

As a reminder to ask yourself these questions, they will sometimes appear in purple.

What if I can’t do it?

Many students are not sure what to say, or think
their answer isn’t good. That is fine, as long as you
try
to think about the question, by typing or saying
the answer to yourself.

Solve for `x`

:

`A`x + `B` = `C`x + `D`

`x =`

[
$("#guessans").val(),
$("#firsttext").val(),
$("#secondtext").val(),
$("#thirdtext").val(),
$("#fourthtext").val()
]

var correct = ( D - B ) / ( A - C );
var solutionDiv = $("<div>").text(correct);
var validator = Khan.answerTypes.number.createValidator(solutionDiv);
return validator(guess[0]);

if (guess != null) {
$("#guessans").val(guess[0]);
$("#firsttext").val(guess[1]);
$("#secondtext").val(guess[2]);
$("#thirdtext").val(guess[3]);
$("#fourthtext").val(guess[4]);
}
else {
$("#guessans").val("");
$("#firsttext").val("");
$("#secondtext").val("");
$("#thirdtext").val("");
$("#fourthtext").val("");
}

an integer, like

`6`

a *simplified proper* fraction, like

`3/5`

a *simplified improper* fraction, like

`7/4`

a mixed number, like

`1\ 3/4`

an *exact* decimal, like

`0.75`

Subtract

from both sides:`C`x

`(`

`A`x + `B`) - `C`x = (`C`x + `D`) - `C`x

`A - C`x + `B` = `D`

What
are you doing or thinking right now?

Why
is what you are currently doing helpful?
Why is it useful for achieving your goal?

How
well is your current approach to this problem
working?

`B > 0 ? "Subtract" : "Add"` `abs(B)``B > 0 ? "from" : "to"` both sides:

`(`

`A - C`x + `B`) + `-B` = `D` + `-B`

`A - C`x = `D - B`

Divide both sides by

.`A - C`

`\frac{`

`A - C`x}{`A - C`} = \frac{`D - B`}{`A - C`}

What
are you doing or thinking right now?

Why
is what you are currently doing helpful?
Why is it useful for achieving your goal?

How
well is your current approach to this problem
working?

Simplify.

`x = `

`SOLUTION`

Subtract

from both sides:`A`x

`(`

`A`x + `B`) - `A`x = (`C`x + `D`) - `A`x

`B` = `C - A`x + `D`

What
are you doing or thinking right now?

Why
is what you are currently doing helpful?
Why is it useful for achieving your goal?

How
well is your current approach to this problem
working?

`D > 0 ? "Subtract" : "Add"` `abs(D)``D > 0 ? "from" : "to"` both sides:

`B` + `-D` = (`C - A`x + `D`) + `-D`

`B - D` = `C - A`x

Divide both sides by

.`C - A`

`\dfrac{`

`B - D`}{`C - A`} = \dfrac{`C - A`x}{`C - A`}

What
are you doing or thinking right now?

Why
is what you are currently doing helpful?
Why is it useful for achieving your goal?

How
well is your current approach to this problem
working?

Simplify.

`SOLUTION` = x