<span>here we can use Pythogoras' theorem.
in right angled triangles the square of the hypotenuse is equal to the sum of the squares of the other 2 sides.
hypotenuse is 19 cm. One side is 13 cm and we need to find the length of the third side.
19</span>²<span> = 13</span>²<span> + X</span>²<span>
X - length of the third side
361 = 169 + X</span>²<span>
X</span>²<span> = 361 - 169
X</span>²<span> = 192
X = 13.85 the length of third side rounded off to the nearest tenth is 13.9 cm</span>
Combinations of 7 taken 4 at a time.
C (7,4) = 7! /[ 4!(3!)]
7 x 6 x 5 = 210
210 divided by 3 = 70
70 divided by 2 = 35
Whenever you are given a scale factor, that factor will apply to each dimension and because area is a two dimensional measurement, you multiply the area by 5 twice (so x5 x5). This means the new area would be 154x5^2. The new area of the photograph is 3850 square inches.
That is why you have an education go to school and learn your anwer.
