Answer:
Step-by-step explanation:
Factorise the denominator of the second fraction
y² - 1 = (y - 1)(y + 1) ← difference of squares
To obtain a common denominator
multiply numerator/ denominator of first fraction by (y + 1)
= -
← subtract numerators leaving the common denominator
=
=
= ← cancel common factor (y - 1) on numerator/denominator
=
Answer:
x = 28
Step-by-step explanation:
If the quadrilaterals are similar, there is a proportionality among their sides:
The top side in the large figure (70) is to the top side in the small figure (10) in the same ratio as the left side (x) in the large figure is to the left side in the small figure (4). This in math terms is written as:
We can then solve for the unknown "x" by multiplying both sides by 4:
Answer:
1) When r = 2, M = 20.
2) When M = 540, r = 6.
Step-by-step explanation:
M is a directly proportional to r cubed
This means that the equation for M has the following format:
In which a is a multiplier.
When r=4 M=160.
We use this to find a. So
So
1) work out the value of M when r=2
When r = 2, M = 20.
2) work out the value of r when M=540
When M = 540, r = 6.