Question

I need help with this.

Answer 1

Hi!

(the green numbers on the image are the step numbers)

We can solve this using PEMDAS.
I wrote out how I solved it in the image, and here I will go more into detail: 

Step 1
Write out the equation

Step 2
Put in the variables

Step 3
Solve:
Parentheses - Multiply

Step 4
Parentheses - Subtract

Step 5 
Multiply

Step 6
Add
There's your answer! :)

The answer is 42

Hope this helps! :)

Answer 2

Substitute the values of a and b

8(3) + 6[2(5)-7]

You have to multiply the numbers in the parenthesis with the adiacent one.

24 + 6(10-7)

24+6(3)

24+18

42