31 and 15
31+15=46
31-15=16
Ratio 4:7
If there are 8 red then number of yellow, y = 8 ×7/4=14
Answer: the rate of the boat in calm water is 9 mph and the rate of the current is 7 mph
Step-by-step explanation:
Let x represent the rate of the boat in calm water.
Let y represent the rate of the current.
A boat goes 32 miles downstream in two hours. Assuming that it travelled in the direction of the current, its total speed would be
x + y mph
Distance = speed × time
Distance covered downstream is
32 = 2(x + y)
16 = x + y - - - - - - - - - - - -1
The return trip against the current takes sixteen hours.
Its total speed would be x - y mph
Distance = speed × time
Distance covered on return trip is
32 = 16(x - y)
2 = x - y - - - - - - - - - - - -2
Adding equation 1 and equation 2, it becomes
18 = 2x
x = 18/2 = 9 mph
Substituting x = 9 into equation 1, it becomes
16 = 9 + y
y = 16 - 9 = 7 mph
Answer:
(x-3)(x-9)
Step-by-step explanation:
first thing you need to do is move the -6 over. so we're going to add 6 to both sides (we add because it's negative 6 and we need 0 on the right side)
so you have: x^2-12x+27
now we need to come up with two numbers that add to -12 and multiply to 27.
the factors of 27 are 9 & 3 and 27 & 1. only 9 & 3 add to 12 so we are going to use those.
since the 12 is negative however, 9 and 3 should both be negative.
therefore we get: (x-3)(x-9)
*it doesn't matter which order you put them in!
