Answer: 28
Step-by-step explanation: you have to add 21 + 7 because your counting up from -7 to 21
Notice the picture below
just use the pythagorean theorem to ge the diagonal
Answer: First option
Step-by-step explanation:
You have the quadratic equation given in the problem:

To find an equivalent expression you cacn factorize. Find two numbers whose sum is -13 and whose product is -30.
These numbers would be -15 and 2.
Therfore, you obtain the following equivalent expression:

If you don't want to apply the method above, you can use the quadratic formula:

Where:

When you susbstitute values you obtain that:

Then you can rewrite the equation as 
Answer:
x=5
Step-by-step explanation:




