3x+15 , this expression correctly combines the like terms
First equation:
5(x+1)=20 —— distribute the 5 to the x and 1
5x+5=20 ——- subtract 5 from 20
5x=15 ———— divide by 5 from both sides
X=3 ————— answer
Second equation:
5x+1=20——— subtract 1 from 20
5x=19 ———— divide by 5 from both sides
X=19/5———— answer in fraction form
X=3.8————- answer in decimal form
When a perpendicular is dropped from the right-angle (C) to the opposite side AB, the metric relations apply:
BD*BA=a^2 ..........................(1)
AD*AB=b^2...........................(2)
BD*DA=DC^2........................(3)
Given AD=6, AB=24, using metric relation (2) above, we have
b^2=6*24=144
=>
b=sqrt(144)=12
By the way, we conclude that this is a 30-60-90 triangle because b/AB=(1/2)=sin(B) => B=30 degrees.
Answer: b=12
5x + 60y = 35
x +y = 1.5 : rewrite as x = 1.5-y and substitute this formula for x in the first one:
5(1.5-y) + 60y = 35
distribute:
7.5 - 5y + 60y = 35
combine like terms:
7.5 + 55y = 35
subtract 7.5 from both sides:
55y = 27.5
divide both sides by 55 to solve for y
y = 27.5 / 55 = 0.5
now substiute 0.5 for y in the 2nd equation:
x + 0.5 = 1.5
x = 1.5 - 0.5 = 1
he walked for 1 hour
Answer:
$99/$115 x 100% = 86.086% of the original price
So 100% - 86.086
= 13.9 = 14%
Or you could just do (115 - 99) x 100 which gets the same answer.
