<span>5(x+1)= 4(x-1)+x
5x + 5 = 4x - 4 + x
5x +5 = 5x -4
5 </span>≠<span> -4
x </span>∈ ∅
Digging -28 would take 16 hours because 14 times 2 equals 28 and 8 times 2 equals 16 so answer is 16
The answer is going to be 87.5%
When ever you have percentages, it should be helpful to bear in mind you can express them as multipliers. In this case, it will be helpful.
So, if we let:
a = test score
b = target score
then, using the information given:
a = 1.1b + 1
a = 1.15b - 3
and we get simultaneous equations.
'1.1' and '1.15' are the multipliers that I got using the percentages. Multiplying a value by 1.1 is the equivalent of increasing the value by 10%. If you multiplied it by 0.1 (which is the same as dividing by 10), you would get just 10% of the value.
Back to the simultaneous equations, we can just solve them now:
There are a number of ways to do this but I will use my preferred method:
Rearrange to express in terms of b:
a = 1.1b + 1
then b = (a - 1)/1.1
a = 1.15b - 3
then b = (a + 3)/1.15
Since they are both equal to b, they are of the same value so we can set them equal to each other and solve for a:
(a - 1)/1.1 = (a + 3)/1.15
1.15 * (a - 1) = 1.1 * (a + 3)
1.15a - 1.15 = 1.1a + 3.3
0.05a = 4.45
a = 89
Given:
diameter = 14 inches
radius = 14 inches / 2 = 7 inches
Circumference of a circle = 2 π r = 2 * π * 7inches = 14 inches * π
Area of a circle = π r² = π * (7in)² = π * 49in²
C = 14π and A = 49π
