Answer:
#3: x is approximately 0.37, -5.37, #4: x is approximately 4.19, -1.19
Step-by-step explanation:
You can solve using the quadratic equation or by solving with the perfect square
= 
x is approximately 0.37, -5.37
2x-x-7=0
3x-7=0
add 7 to 7 and 0, so then we cross out 7-7, and then
3x=7, bc u change the subtraction to addition, sr if thst doesn't make sense but 3x=7 is the answer
Answer:
53/100?
Step-by-step explanation:
I mean you can't really simplify it any more. There's no LCD, GCD. Can't divide it evenly.
To solve it I just looked at the number of places, (3 which mean 100.)
Then I looked at the numbers, (53.)
So you just turn that into a fraction...
Answer:
20 hours
Step-by-step explanation:
We can work easier if we think in terms of an hour
the first equation that we can write is
A + B = 1/4 (its meaning is that in an hour A and B fill 1/4 of the cistern)
the second equation we can write is
A + C = 1/5 (its meaning is that in an hour A and C fill 1/5 of the cistern)
the third equation that we can write is
B = 2C (its meaning is that in an hour B fill 2 times C the cistern)
now we can substitute the value of B in the first two equations
A + 2C = 1/4
A + C = 1/5
A = 1/5 - C
1/5 - C + 2C = 1/4
C = 1/4 -1/5
C = (5-4)/20
C = 1/20 (this means that in an hour C will fill 1/20 of the cistern, so it takes 20 hours to fill the entire cistern)
A = 1/5 - 1/20
A = (4-1)/20 = 3/20
B = 1/20 *2 = 1/10
