The summation symbol means we use the variable i in the equation from the given range. In this case, we are given with the equation 3 i - 15 and i ranges from 2 to 7. The summation using simply the calculator is equal to -9. The answer to this problem is -9.
adding 320,294,265 and 301=1180
4 divided by 1180=answer 295
Answer: m²-9mn+2n²
Step-by-step explanation: make use of BODMAS strategy. Let the unknown be x.
-7mn+2m²+3n²-x= m²+2mn+n². Since we are concerned about getting the unknown,let's try to collect the like terms.
-7mn+2m²+3n²-(m²+2mn+n²)= x
-7mn+2m²+3n²-m²-2mn-n²= x
-7mn-2mn+2m²-m²+3n²-n²=x
-9mn+m²+2mn= x
X= m²-9mn+2n²