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# i need help

8+3*5-4^2 , 17+28 divided by (5+9 times 1)+2^2 ,12a+4-10a^2 , 4x+4+x+12y-10y (its very hard )

8 + 3 * 5 - 42    ---> 8 + 15 - 16 ---> 7

17 + 28/(5 + 9 * 1) + 22   ---> 17 + 28/14 + 4 ---> 17 + 2 + 4 --->  23

12a + 4 -10a2 ---> cannot simplify  anymore

4x + 4 + x + 12y - 10y  ---> 5x + 2y + 4

Let's start with the first problem: 8 + 3 x 5 - 4^2

I don't know if you were ever taught PEMDAS.  It gives you the order of operations in these types of problems. Parentheses, Exponents, Multiplication, Division, Addition, Subtraction.  That is the order in which you solve this type of problem. So, the first thing to do is your exponent 4^2, which = 16

8 + 3 x 5 - 16

Next, we have Multiplication of 3 x 5 = 15;

8 + 15 - 16

Now, we can do the Addition of 8 + 15 = 23

23-16

The final step is Subtraction of 23 - 16 = 7.  Follow PEMDAS and do each step to make it easier.

Next question: 17 + 28/(5 + 9 x 1) + 2^2

Parentheses first (5 + 9 x 1). Even within this problem, follow PEMDAS, so multiplication will be done before addition; therefore, 9 x 1 = 9, 5 + 9 = 14

17 + 28/14 + 2^2

Next, Exponent 2^2 = 4

17 + 28/14 + 4

There is no multiplication, so Division is next 28/14 = 2

17 + 2 + 4

Last step, Addition 17 + 2 + 4 = 23

Question 3: 12a + 4 - 10a^2; you will still use PEMDAS to do like terms

Exponent first  10a^2 is the same as 10a x 10a (10 x 10 = 100) and (a x a = a^2); so it is 100a^2

12a + 4 - 100a^2

That is as far as you can go, unless you put them in order.  If so, it would be -100a^2 + 12a + 4.

Question 4: 4x + 4 + x + 12y - 10y

In this problem, you are putting like terms together;

4x + x = 5x

So, you have 5x + 4 + 12y - 10y

Now, 12y - 10y = 2y

So, you have 5x + 4 + 2y or in order of variable, it would be 5x + 2y + 4.  That is as far as you can go.

I hope these explanations help.  Good luck