5^x=5 ⇔ x=1
2^x=2^7 ⇔ x=7
4^x=16 ⇔ 4^x=4^2 ⇔ x=2
7^x = 1 ⇔ x = 0
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x+5=25|-5 ⇔ x =20
x-36=4|+36 ⇔ x=40
5x=30 |:5 ⇔ x=6
2(x=3) = 14 |:2 ⇔ x+3 = 7 ⇔ x =4
3(x-2) =24 |:3 ⇔ x-2=8 ⇔ x = 10
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x≤ 0 ⇒ S= (-∞, 0]
x-3 > 7 |+3 ⇔ x>10 ⇒ S= (10, ∞)
3(x+2) ≤ 27 |:3 ⇔ x+2 ≤ 9 |-2 ⇔ x ≤ 7 ⇒S = (-∞, 7]
