(r + 10)(r - 4)
To double check:
r * r is r^2
10 * r = 10r; -4 * r = -4r
Combine to get 6r.
-4 * 10 = -40
Since a total of 55 people rated it good/very good, we know that 1/3 of the viewers are 55 people. So we can set the equation: 1/3x=55
Now, just multiply both sides by 3 (or divide by 1/3, same thing) and get your answer!
point slope equation formula: y - y1 = m (x - x1)
(-1,4) (-2,1)
answer:
1 -4 = 3 (-2+1)
This question is a little tricky. Carla had a bill of $15, which we will add to the cost of Rob's lunch. They left a 20% tip on the TOTAL cost of both their lunches, which should equal $6. 20% is equivalent to 0.2. So, the equation is 6=0.2(x+15). In other words, 20% of the sum of Carla and Rob's lunches is 6 dollars.
Answer: 6=0.2(x+15)
