Answer:
6x² (2x - 5)
Step-by-step explanation:
12x³ - 30x²
= 6x² (2x - 5)
115% is the same as 1.15
some number = x
115% of some number is 120
1.15 of x is 120
1.15 * x = 120
x = 104.3478
<span>x ≈ 104.3</span>
280 yards are equal to 840 feet
Answer: you have $31 at the end of the week
Step-by-step explanation:
First, let's put this problem into an algebraic expression. We started off with $42. We then added $25 and took out $36 during the week. The expression for this problem is
42
+
25
−
36
.
Next, add 42 and 25 together to get
67
. We now have
67
−
36
.
Finally, subtract 36 from 67 to get
31
, our answer.
You problem is you don't have any problem. You have a bunch of formulas for the perimeter and area of some shapes.
As for using the formulas, usually you're given all but one of the variables and you can solve for the remaining one.
Notice how the triangle result doesn't have area as a function of a, b and c. That's called Heron's formula and is usually not taught to secondary school students. I don't like to teach it either because Archimedes' Theorem is so much better:
The sides a,b,c and area S of a triangle satisfy
