Algebra help!?

Question

9(-7) - 6(-7)^2 + 4(2)^2 is:
-63 - 294 + 16.

If I start from largest to smallest to solve this I would do 294 + 16 =310. So then I'm left with -63 - 310. But if you have a negative number minus a positive number you subtract right? so (neg - pos = subtract) -63-310= -373. Which turned out to be wrong. The right way would of been -62 - 294 + 16 = -341.

If the following charts I have are true, what am I doing wrong?

Adding intergers

Negative + Negative = (add)
Positive + Positive = (add)
Negative - Negative = Add (add as written)
Positive - Positive = (Subtract)
Negative + Positive = (add)
Positive + Negative = (subtract)
Negative - Positive = (Subtract)
Positive - Negative = (add)

Positive squared = positive
Positive cubed = positive

Integers & powers
Negative squared = positive
Negative cubed = negative
Positive multiplied by positive = positive
Negative multiplied by negative = positive
Negative multiplied by positive = negative
Positive multiplied by negative = negativ

I'm studying for my GED, and math is the only thing I need to work on I really need the help! Because I know algebra is on test.

Answer 1

Solve: 9(-7) - 6(-7)^2 + 4(2)^2

*Solve the expression according to order of operations called, PEMDAS.... ( ), exponents, multiplication, division, addition & subtraction.

9(-7) - 6(-7)(-7) + 4(2)(2)

9(-7) - 6(49) + 4(4)

- 63 - 294 + 16

- 63 - 278

= - 341

Answer 2

You got all the complicated calculations right, just the last -63 - 294 + 16 is incorrect.

Stick to the rules you have and you will be able to reach this stage however, when adding and subtracting numbers like in your example, use a simple rule like:

add all negative numbers
add all positive numbers
subtract the 2 previous numbers and always give the sign of the highest of the 2 numbers

in your example:

add all negative numbers 63+294=357
add all positive numbers 16
subtract the 2 of them 357-16=341

and always give the sign of the highest addition,

in this case the negative addition is higher hence the result is
-341

Answer 3

Just solve left to right.

-63 - 294 + 16
= -357 + 16
= -341

You don't need to do that "largest to smallest thing". If all the operations are addition/subtraction, it isn't necessary.

Answer 4

You seem to be mixed up about adding and subtracting signed numbers. Remember this simple rule for subtracting: Change the sign of the subtracted number and then add the numbers.

Example One: 10 - (-20) = 10 + 20 = 30
Example Two: 10 - (+20) = 10 - 20 = -10

It helps to use the parenthesis around the number your subtracting to remind you to change the sign and add.

Answer 5

For increasing cubic binomials the regularly occurring formulation is as follows: (a + b) ^ 3 = a^3 + 3*a^2*b^a million + 3*a^a million*b^2 + b^3 on your case, a is x and b is -y^5 So (x - y^5)^3 = x^3 + 3*x^2*(-y^5)^a million + 3*x^a million*(-y^5)^2 + (-y^5)^3 Simplified: =x^3 - 3x^2*y^5 + 3x*y^10 - y^15 :D

Answer 6

Far too many details for this forum. Get a math tutor or go to a class at night school.