Answer:
a: 
Step-by-step explanation:

Expand:



Subtract:

Answer:
x : y = 9 : 13
Step-by-step explanation:
Given that
3x - y : x + 2y = 2 : 5
Express the ratio in fractional form, that is
=
( cross- multiply )
5(3x - y) = 2(x + 2y) ← distribute parenthesis on both sides )
15x - 5y = 2x + 4y ( subtract 2x from both sides )
13x - 5y = 4y ( add 5y to both sides )
13x = 9y ( divide both sides by 13 )
x =
y ( divide both sides by y )
=
, that is
x : y = 9 : 13
Answer:
3ft
Step-by-step explanation:
We are given that
Height of lamp, h=12ft
Height of shadow, l=6ft
Height of shadow of hydrant, l'=1.5ft
Let height of hydrant=h'
We have to find the height of fire hydrant.
All right triangles are similar
When two triangles are similar then, the ratio of their corresponding sides are equal.
Using the property



ft
Hence, the height of fire hydrant=3 ft