The restrictions for the equation is that the denominator can not be zero. So the restrictions for x would be what values make the denominator zero.

7x^2 + 6x = 0
factor
x(7x + 6) = 0
multiply any number by 0 and you get 0. So either x = 0 or 7x+6 = 0
since there's a x in the numerator x/x = 1 so this will not be a restriction. Then the only restriction is:
7x+6 = 0
7x = -6
x = -6/7

5 0

2 years ago

Water flows through a pipe of diameter 4cms with a velocity of

MissTica

Answer:

1.28 m

Step-by-step explanation:

The speed at which water rises in the tank is proportional to the speed of the water in the pipe and inversely proportional to the ratio of the tank area to the pipe area.

The ratio of tank area to pipe area is the square of the ratio of their diameters:

((150 cm)/(4 cm))² = 1406.25

Then the rate of rise of water in the tank is ...

(0.5 m/s)/(1406.25)

After 1 hour = 3600 seconds, the height of the water will be ...

rise = (time)(rate of rise)

(3600 s)(0.5 m/s)/1406.25 = 1.28 m

4 0

2 years ago

A test has two parts, A and B, each containing 10 questions. A student needs to choose 8 questions from part A and 4 questions f

Tpy6a [65]

Part A number of combinations of 8 from 10 = 10C8 = 10C2

= 10*9 / 2 = 45

Part B Number combinations = 10C4 = (10*9*8*7)/ (4*3*2) = 210

Total number of ways = 45 * 210 = 9450 (answer)

3 0

3 years ago