
By the quadratic formula,

Then


Multiply numerator and denominator by the denominator's conjugate:

<span><span>The sum of a squared and b is given by

</span>7 times the sum of a squared and b is given by
</span><span>
while 4 times the sum of a squared and b is given by
</span>

Therefore, <span>7 times the sum of a squared and b minus 4 times the sum of a squared and b is given by

</span>
Since ur using r as a variable the answer is r = 7.
66 more min. he used which could be 1 hour and 6 min.
Answer:
-
Step-by-step explanation:
a minus sign.