Respuesta :

Answer:

see explanation

Step-by-step explanation:

(a)

the area( A ) of a trapezium is calculated using the formula

A = [tex]\frac{h}{2}[/tex](a + b)

where a and b are the lengths of the parallel sides and h is the perpendicular height between them

here a = 13x, b = 17x + 12 and h = 5

A = [tex]\frac{5}{2}[/tex](13x + 17x + 12) = [tex]\frac{5}{2}[/tex](30x + 12)

A = 5(15x + 6) = 75x + 30 cm²

(b) ΔABC is a right triangle so we can use the sine ratio to solve for y

We require to find BC using Pythagoras' identity

BC² = 5² + 12² = 25 + 144 = 169

⇒ BC = [tex]\sqrt{169}[/tex] = 13, hence

sin y° = [tex]\frac{opposite}{hypotenuse}[/tex] = [tex]\frac{5}{13}[/tex]

⇒ y = [tex]sin^{-1}[/tex]([tex]\frac{5}{13}[/tex]) = 22.6° ( to 1 dec. place )