Am trying to find the value of r

1/r + 2/1-r = 4/r^2

What is (3/10 being a fraction) 5 3/10 - 7.8

You roll two dice what is the probability that the sum of the dice is less than 5 and one dice shows a 2? ... ?

The decimal i am thinking of is 3 tenths greater than 80%. What is my decimal

For each handmade greeting card jacqui sells, she makes a profit of $0.35. In one week, she madea profit of $42. She sells the card for $0.75 each. About how many cards did jacqui sell that week

Find the second and third term of the arithmetic sequence - 7, _, _, - 22, - 27, ... A. - 12, - 15 B, - 17, - 12 C. - 10, - 17 D. - 12, - 17

How many times would it take to walk 1,000,000 yards in a park that is 150 yards on one side and 125 on the other

8y-36 factor the expression complete

Find the volume of a box that will hold nine 9.425 cm3 cylindrical containers that each measure 3 centimeters long. (round to nearest whole number)

What is the explicit formula for this sequence? 2, 10, 50,250, 1250 ...

A fruit salad contains 25 blueberries and 20 raspberries. What is the ratio of blueberries to raspberries in the fruit salad? A. 4:9 B. 5:4 C. 4:5 D. 5:9