What algebraic expression must be added to the sum of 3x2 +4x+8 and 2x2−6x+3 to give 9x2−2x−5 as the result?

4x² - 16 is the algebraic expression that must be added to get the result as 9x²- 2x - 5.

Step-by-step explanation:

The question is asked for the algebraic expression must be added to the sum of 3x²+4x+8 and 2x2−6x+3 to give 9x²- 2x - 5 as the result.

Therefore,

The first step is to find of sum of 3x²+4x+8 and 2x²-6x+3.

To find the sum :

3x²+4x+8

2x²-6x+3

5x²-2x+11

The sum is 5x²-2x+11.

Now, the second step is to subtract 5x²-2x+11 from the result 9x²- 2x - 5.

  9x²- 2x - 5

- (5x²-2x+11)

  4x²    -16

Thus, 4x²-16 is the algebraic expression that must be added with 5x²-2x+11 to get a result of 9x²- 2x - 5.

option c) graph of line going through 1, 4 and 3, 10

step-by-step explanation:

let y equal to margo's coin collection

let x equal to number of years

at the begining x=0, y=1 → point=(x,y)→point=(0,1)

she adds 3 coins per year, then y=1+3x

at x=1, y=1+3(1)=1+3→y=4→point=(x,y)→point=(1,4)

at x=3, y=1+3(3)=1+9→y=10→point=(x,y)→point=(3,10)

the graph of line going through (1, 4) and (3, 10), then the option c is the correct.

this may not be at all, but i use the same website you're using for school, and if i'm stuck doing one of these i try to look for it on the section.