Tolong dijawab juga yaa soal nya besok di kumpul:) makasii

a.
= 10 x (2y - 10)
= 20y - 100
20y = 100
y = 100 ÷ 20
y = 5

b.
= (x + 5) x (5x - 1)
= 5x² - x + 25x - 5
= 5x² + 24x - 5

c.
= (7 - 2x) x (2x - 7)
= 14x - 49 - 4x² + 14x
= -4x² + 28x - 49


Maaf kalau benar ya kak...
Let's math every^DAMN^day!
[DAMNATION]™