Kak bantu kak yg no 1 a-c

a. (10 × 2y) + ( 10 × (-10))
20y - 100

b. (x × 5x) + (x × (-1)) + (5 × 5x) + (5 × (-1))
5x^2 - x + 25x - 5
5x^2 + 24x - 5

c. (7 × 2x) + (7 × (-7)) + (- 2x × 2x) + (-2x × -7)
14x - 49 - 4x - 2x^2 + 14x
-2x^× + 24x - 49

a. 10 × (2y-10)= 10×2y-10×10
=20y-20
b.(x+5)×(5x-1)=X×5+X×-1+5×5+5×-1
=5x+-X+25+-5
c.(7-2x)×(2x-7)=14x-49-4x•+14x
•=pangkat 2
maaf kalo salah