You equal each to zero, so -6,0,3,7
5.392 is 5.39 rounded to the nearest hundredth
Answer:
1)
.
2) 
hence, answer is 7/12.
3) We have to divide £72 in the ratio 2:3:1
the total of the ratio is=2+3+1=6
so on dividing 72 into 6 parts we have 72/6=12
First '2' parts=2×12=24
second '3' part=3×12=36
last '1' part=1×12=12
so dividing £72 in the ratio 2:3:1 is: £24,£36 and £12
4) 39 people out of 65 have blonde hair.
Number of people who do not have blonde hair=65-39=26
percentage people who do not have blonde hair is given by:

Hence, percentage people who do not have blonde hair is 40%
5) 20% of 90= (20/100)×90
=18
Hence, 20% of 90 is 18.
6) Factorise

7) Expand

8)
.
9)

10)

11) x= -4 y=3
and z=4 x-y^3
z=4×(-4)-3^3
z= -43
12) 
13) 
Hence x= -2
14) 5,10,15,20,....
Hence, nth term is 5n.
15) (63×128)/32.9=245.106.
16) 938×21=19698.
Let,the time taken by larger pipe = x
By smaller pipe = x+5
It would be: 1/x + 1/(x+5) = 9/100
= x+5+x /(x)(x+5) = 9/100
= 2x+5 / x²+5x = 9/100
= 100(2x + 5) = 9(x² + 5x)
= 200x + 500 = 9x² + 45x
= 9x² - 155x - 500 = 0
= 9x² - 180x + 25x - 500 = 0
= 9x(x - 20) + 25(x - 20) = 0
= (9x + 25) (x - 20) = 0
= x = -25/9 or x = 20
Time can't be in negative so -25/9 is rejected.
Now,x + 5 = 20 + 5 = 25
In short, Your Larger pipe takes 20 minutes and smaller pipe takes 25 minutes
Hope this helps!
The answer is 644 bescause 23 times 4 is 92 and then 92×7 is 644