I DONT UNDERSTAND I NEED HELP

Ametalworker has a metal alloy that is 30? % copper and another alloy that is 55? % copper. how many kilograms of each alloy should the metalworker combine to create 90 kg of a 50? % copper? alloy?

[15 points]find the least common multiple of the expressions: 1. 3x^2, 6x - 18 2. 5x, 5x(x +2) 3. x^2 - 9, x + 3 4. x^2 - 3x - 10, x + 2 explain if possible

The coordinates of vortex a’ are (8,4) (-4,2) (4,-,4) the coordinates of vortex b’ are (6,6)(12,-,12)(12,12) the coordinates of vortex c’ are(-2,,12)(4,12)(12,-4)