What is the value of r in the equation 4r − 8 = 5r + 12?

2 answers:

6 0

To find r, we have to isolate it on one side of the equation. We can do this by "undoing" the equation one step at a time.

4r - 8 = 5r + 12

4r - 8 - 4r = 5r + 12 - 4r

-8 = r + 12

-8 - 12 = r + 12 - 12

-20 = r

r = -20

Hope this helps!

Kipish [7]2 years ago

5 0

Answer:

r= -20

Step-by-step explanation:

you need to solve this equation for the variable r, which means you need to get r alone on one side of the equation.

4r-8=5r+12

subtract 4r from both sides

-8=5r-4r+12

-8=1r+12

subtract 12 from both sides

-8-12=r

simplify

-20=r

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Explanation:
Below is the graph attached of both the equations:

Red line: Represents f(x) = 2x + 2.
Blue line: Represents g(x) = 2x - 3.

As you can see in the graph that g(x) is shifted 5 units right to f(x).

If you move towards right by 1 unit, you have to subtract 1 from f(x) until you reach g(x) like:
2x + 2 - 1 = 2x + 1 (1 unit)
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Total 5 units.

Hence the correct answer is the graph shifts 5 units right.