Solve using the multiplication principle.

-4/5x=16/35.
(5)-4/5x=16/35(5)
-4x=180/175
Now I'm lost. What do I do now? Thanks.

After multiplying both sides by 5, you should have obtained

-4x = 16/7
Next, multiply both sides by -1/4.
x = -4/7

Great job using the multiplication principle to solve the equation so far! Now, let's continue solving.

To simplify the equation further, we can multiply both sides by the reciprocal of -4, which is -1/4. This will eliminate the coefficient on the left side of the equation, leaving us with x.

(-1/4)(-4x) = (-1/4)(180/175)

The negative sign cancels out on the left side, so we're left with:

x = (-1/4)(180/175)

To multiply fractions, we multiply the numerators together to get the new numerator, and multiply the denominators together to get the new denominator:

x = (-180/4)/(175/1)

Now, we can simplify by dividing the numerator by the denominator:

x = -45/1

Simplifying further, we have:

x = -45

Therefore, the solution to the equation -4/5x = 16/35 is x = -45.

Remember to always simplify your fractions as much as possible and double-check your work. Keep up the great work!