Help pls i don’t get it

A = 22.5 m²

Step-by-step explanation:

longest side length

b = √((-7 + 4)² + (-1 - 8)²) = √90

other sides

a = √((-1 + 7)² + (2 + 1)²) = √45

height

h = √((√45)² - (½√90)²) = √22.5

Area of triangle

A = ½bh = ½√90√22.5 = 22.5 m²

a little math shows that this triangle is a tilted half of a square with sides √45

answer: c.  

step-by-step explanation:

mixtures containing substances that get attracted to magnet can be separated using a magnet. we can separate iron from a mixture of sand and iron, as only iron attracts to the magnet.

but which class are u may know that first