Teacher d may be convenient for you to remember.

therefore

Let's explain it with the cross multiplication on the left. In fact,

The principle is as follows: suppose there is an equation. y/5 = (4+y)/6。 First of all,

You see that the denominators on the left and right sides of the equal sign are 5 and 6. Step one.

Our purpose

The way to eliminate these denominators is on both sides of the equal sign.

Multiply by 5X6 at the same time.

(y/5)X5X6 = [(4+y)/6]X5X6 Step 2

Our purpose

Is to simplify both sides of the equal sign.

(y)X6 = (4+y)X5。 Do you see it? The denominator 5 on the left has been removed.

(y) Denominator 6 to the right of y)X6 is eliminated.

The remaining (4+y)X5 goes to this step.

Denominator 6 is on the right

Multiply the molecule y on the left. The denominator on the left is 5.

Multiply by the molecule on the right (4+y). This is "cross multiplication". You can keep doing it.

See if you can get the answer .. y = 20.

Cross multiplication is used for fractions/proofs, for example: 1/4=z/8, 4Xz, 8X 1, 4z=8 z=2.

Reference: self

For example, (3/x)= 1/4 times 3 and 4 and x and13x4 = x112 = x multiplies the denominator on the left by the numerator on the right, which is called cross multiplication.