Question

Which expression is equivalent to 21 + 49?

a) 7(3 + 49)
b) 7(3 + 7)
c) 7(14 + 42)
d) 7(14 + 49)

Answer 1

@dontsaymyname i need help.

Answer 2

what is a common factor between 21 and 49?

What numbers multiply to 21 and what numbers multiply to 49?

Answer 3

idk

Answer 4

Here's an example

12
What numbers multiply to 12?

1 * 12 = 12
2 * 6 = 12
3 * 4 = 12

So all the numbers that multiply to 12 (or we could call them factors) would be

1, 2, 3, 4, 6, and 12

Answer 5

So what are all the factors, or all the numbers that can multiply to get you 21?

Answer 6

3 7

Answer 7

Good, there's also 1 and 21 but you got the important ones for now

What about for 49?

Answer 8

yes

Answer 9

wait is it D

Answer 10

You almost got the idea. But we're looking at numbers that multiply to get us the original number. We're not adding/subtracting.

Have you seen the distributive property before?
a(b + c) = ab + ac

We would multiply that number inside. If we take that number outside so like if we have
ab + ac

We would have to divide each number by `a` so we could put it outside like a(b+c)

Answer 11

ok so, it must be what two numbers get me to 21

Answer 12

Here's another example

55 + 77

Another way to write 55 is 5*11
Another way to write 77 is 7*11

55 + 77 = (5*11) + (7*11)

Both numbers have 11 as a common factor so we can pull it out and we get
11 * (5+ 7)

Does that make sense?

Answer 13

its b then

Answer 14

Good

Answer 15

You got it!

Answer 16

finally

Answer 17

can i let u know when i need help?

Answer 18

Sure. You can make a new post and tag me :)

Answer 19

ok

Answer 20

the answer is b because 7 + 3 = 10 and 10 times 7 is 70

so B is your answer