700 times 3 is 2,100, You get 700 from estimating 697
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 
If its 21 inches then rounding to the nearest who should be 21 inches
Answer:
17
Step-by-step explanation:
There is a SUBTRACTION symbol in the problem. So, you will do the opposite, & ADD the 2 available numbers in the equation. 10+7=17
When you replace that y with 17, the equation is correct.
Answer:
25/72
this can be solved by finding a great common factor