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How do you solve #9/4=(r-10)/r#?

Answer 1

Savannah Anderson

#r=-8#

#9/4=(r-10)/r#

Start by multiplying by a cross.

#(9)(r)=4(r-10)#

#9r = 4r - 40#

Add #-4r# on both sides

#9r - 4r = 4r - 40 - 4r#

#5r = -40#

Divide both sides by #5#

#(cancel5r)/cancel5=(-40)/5#

#r=-8#

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Answer 2

Abigail Allen

To solve the equation ( \frac{9}{4} = \frac{r-10}{r} ), you can cross multiply to eliminate the fractions. Multiply (9) by (r) and (4) by (r-10). This gives you (9r = 4(r-10)). Then, distribute the (4) on the right side, giving you (9r = 4r - 40). Subtract (4r) from both sides to isolate (r), resulting in (5r = -40). Finally, divide both sides by (5) to find (r), which equals (-8).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.