Answer:
4
Step-by-step explanation:
You need to try out all the numbers.
lets start with 4
if there where 4 red marbles then there would be 9 times as many marbles
so 4 x 9 = 36
Now we add and see if the sum is 40
36 + 4 = 40
We got it on the first try
You can use the same method on more problems like these.
Hope this helps :)
Answer:
-11, 11
Step-by-step explanation:
You have to find when the function crosses the x-axis. You could find this using algebra by solving for x in the equation but I prefer to simply graph it using something like desmos and see when it crosses the x-axis. Doing that I can see the answers would be -11 and 11
Answer:
15 inches
Step-by-step explanation:
Perimeter is 2l + 2w (or l+l+w+w)
Start by subtracting: 42 - 12. The 12 is from 2•6 for both width sides.
42-12=30
Divide 30 by 2 to find the length for one side. 30 ÷ 2 = 15
Here's my work shown for question 1 and 2
