Simply collect like terms, numbers and or variables that have the same number and type of variable.
For example 15x^2 and 10x^2 are like terms. Circle the sign in front of the term to perform the correct operation.
Given :
A 136 foot tall cell phone tower casts a 79.9 foot shadow.
To Find :
The shadow length for a nearby 40 foot telephone pole .
Solution :
We know , the ratio of height and shadow , will be same for every object .
Let , length of shadow of pole is x .
So ,

Therefore , the length of shadow of tower is 23.5 foot .
Hence , this is the required solution .
20% is the amount takin off of the sofa
It takes 4.3 seconds for the rocket to return to earth.
The equation is:

where -9.8m/sec² is the acceleration due to gravity, v₀ is the initial velocity, and h₀ is the initial height. We will go from the assumption that the rocket is launched from the ground, so h₀=0, and we are told that the initial velocity, v₀, is 42. This gives us:

We will use the quadratic formula to solve this. The quadratic formula is:

Plugging in our information we have:

x=0 is when the rocket is launched; x=4.3 is when the rocket lands.