20% = 0.20
800 * 1.20 = 960
total cost = £960
Let's call the solutions x₁ = (5 - 2√7)/3 and x₂ = (5 + 2√7)/3
Then the equation is (x-x₁)(x-x₂) = 0
If you fill that in you get a lot of numbers which you can recognize as ax²+bx+c=0.
You can see that a=1 (there is just an x²)
b = (-5 -2√7 + 2√7 - 5)/3 = -10/3
c = ((-5-2√7)/3 ) * (-5+2√7)/3) = -1/3
So the equation you're looking for is:
Answer:
Step-by-step explanation:
I think you're asking how we use formulas to find areas and volumes.
There's no one area formula; the formula we use to calculate an area depends upon the shape.
For example, the area of a square of side length s is A = s^2.
The area of a triangle with base b and height h is (1/2)*b*h.
Similarly, the choice of formula for the purpose of calculating voume depends upon the shape of the 3-dimensional object.
For example, the volume of a cube with side length s is V = s^3.
The volume of a cylinder with radius r and height h is V = (1/3)πr^2*h.
Answer:
1. Along a diagonal, and then along an edge.
2. 48.28 cm.
Step-by-step explanation:
Assume points A and B are at diagonally opposite corners, as in the diagram below.
1. Shortest path
The shortest path is to go along the diagonal AC and continue along the edge CB.
2. Distance
The distance travelled is
d = AC + CB
According to Pythagoras,
AC² = AD² + CD² = 20² + 20² = 400 + 400 = 800
AC = √800 = 20√2
d = AC + CB = 20√ 2+ 20 ≈ 2 × 1.414 + 20 = 48.28 cm
The ant travels 48.28 cm.