Evaluate the expression for a = -1 and b = 5. show your work.
5a - 7b +b²

Question

Evaluate the expression for a = -1 and b = 5. show your work.
5a - 7b +b²

fibonaccichick666 · Answer

what do you think you need to do to start?

anonymous · Answer

substitute a=-1 and b=5 into the equation

anonymous · Answer

5x-1 - 7x5 +5²??

princeharryyy · Answer

5*(-1) -7*5 + 5*5 = -5 - 35 +25 =-15

fibonaccichick666 · Answer

ohoh ok they are multiplications ok yea so now, what do you do first by the order of operations?>

anonymous · Answer

no clue

princeharryyy · Answer

@AngelofVengeance6661

fibonaccichick666 · Answer

ok so can you tell me the order of ops angel?

anonymous · Answer

no this is my brothers problem i sucked at algebra. and so does he

fibonaccichick666 · Answer

ok so you need to check out the order of operations to begin this, do you remember PEMDAS or Please Excuse My Dear Aunt Sally?

anonymous · Answer

yeah a little

fibonaccichick666 · Answer

if not it's ok, we can review

anonymous · Answer

parenthesis
exponet
multiply
divide
add
subtract

fibonaccichick666 · Answer

so give this a quick read for me, and one other favor, when you substitute put parentheses around the numbers you are inputting

fibonaccichick666 · Answer

http://www.purplemath.com/modules/orderops.htm

fibonaccichick666 · Answer

when you come back, tell me what you think you need to do first

fibonaccichick666 · Answer

$$5(-1) - 7(5) +(5)^2$$

anonymous · Answer

im still lost

anonymous · Answer

should he show the parenthesis you just applied above?

anonymous · Answer

$$=-5-35+25$$

anonymous · Answer

=?

anonymous · Answer

55?

anonymous · Answer

solve it @AngelofVengeance6661

anonymous · Answer

nope

fibonaccichick666 · Answer

yea, reason being is that it helps stop mistakes

anonymous · Answer

$$=-40+25$$

fibonaccichick666 · Answer

so now, by order of operations, what will you do first?

anonymous · Answer

-15?

fibonaccichick666 · Answer

just, work through with me and you'll getthe answer and understand it

anonymous · Answer

exponets?

fibonaccichick666 · Answer

yes, so just baby steps here, can you simplify our exponent term $$5(-1) - 7(5) +(5)^2$$

anonymous · Answer

25

fibonaccichick666 · Answer

so then, what are we left with?

anonymous · Answer

i think i may understand. im ocd so when it says parenthesis first and there arent any parenthesis i lose my mind completely

fibonaccichick666 · Answer

ahh ok, well, there are invisible parentheses around the whole thing if it makes you feel better :)
But anyways we have $$5(-1) - 7(5) +(5)^2=5(-1) - 7(5) +25$$ right?

anonymous · Answer

5(−1)−7(5)+(5)2
-5 - 35 +25
 -40 +25 = -15

fibonaccichick666 · Answer

very good

fibonaccichick666 · Answer

do the steps make sense?

anonymous · Answer

yes. thank you

fibonaccichick666 · Answer

np, happy it makes sense.  Thank you for wanting to learn.  Please feel free to tag me when learining is the goal :)

anonymous · Answer

deffinitely will have a few more tonight.

fibonaccichick666 · Answer

np if I'm awake, just tag me