The expression means the product of 5 and the difference of three times r minus 10. if r = 4, the value of the expression is

10

Step-by-step explanation:

5 · (3r - 10)

If r = 4, this expression becomes 5 · (3[4] - 10), or 60 - 50, or 10.

to find the perimeter of the rectangle this is the expression:

x-9+x-9+3x-4+3x-4=138

if we simplify it:

8x-26=138

remember, 138 is what it all adds up to

the length is 11.5cm

the width is 57.5cm

the area is 661.25cm^2

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