How do you make the delta symbol using the keyboard? know, the triangle thing. i couldnt figure out where to put this question, so its going here

Sienna planned a trapezoid-shaped garden, as shown in the drawing below. she decides to change the length of the top of the trapezoid-shaped garden from 32 ft to 24 ft. which expression finds the change in the scale factor?

What is the expression in factored form? 225x^2 - 144 a. 9(5x+4)^2 b. 9(5x-4)^2 c. 9(4x+5)(4x-5) d. 9(5x+4)(5x-4)

Simplify. 4+3/7x-2-2/7x a. 2-5/7x b. 6-1/7x c. 2+1/7x d. 6+5/7x