I think the surface area and factoring are the most difficult concept for me.
question 1. solve the surface area of a 6cm cube
6(6×6) = 6(36) = 216. so the answer is 216 cm.
question 2. simplify (3x+ 4)(2x+3) and (x+6)(2x-4), and solve x²-7x+6.
(3x+ 4)(2x+3) = (3×2)x²+(3×3+2×4)x+3×4 = 6x²+(9+8)x+12 = 6x²+17x+12
(x+6)(2x-4) = (2×1)x²+(1×-4+6×2)x+6×-4 = 2x²+(12-4)x-24 = 2x²+8x-24
x²-7x+6 = (x-6)(x-1)
factoring
link: https://www.youtube.com/watch?v=eF6zYNzlZKQ
surface area (rectangular prism)
link: https://youtu.be/lm46kqCDWaI