What is the correct answer for 3r - 3p + 5q if p = 4, q = -2, r = 3, and s = -5?

Thread starter Gringo123
Start date Feb 24, 2010
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To evaluate the expression 3r - 3p + 5q with the values p = 4, q = -2, and r = 3, the calculation proceeds as follows: 3(3) - 3(4) + 5(-2) results in 9 - 12 - 10. The correct answer is -13, confirming the math book's solution. The initial miscalculation of -7 arose from incorrect arithmetic in combining the terms. The final evaluation clearly shows that the accurate answer is indeed -13.

Feb 24, 2010

Gringo123

p = 4
q = -2
r = 3
s = -5

on that basis, evaluate this expression:

3r - 3p + 5q

I make it to be -7 (15 - 12 + (-10)
But my math book says the answer is -13. Can anyone explain where I have gone wrong?
Thanks

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Feb 24, 2010

snshusat161

3r - 3p + 5q

= 3(3) - 3(4) + 5(-2)

= 9 - 12 -10

= -13

Feb 24, 2010

Gringo123

Thanks!

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