Question

1)Tìm x:

a.(15.x+2.2³)-4=10

b.3.x.15⁵=15⁶

Answer 1

a) ( 15x +2.2\(^3\)) -4=10

\(\Rightarrow15x+2^4=14\)

\(\Rightarrow15x=14-16\)

\(\Rightarrow x=\left(-2\right):15\)

\(\Rightarrow x=-\frac{2}{15}\)

b)\(3x.15^5=15^6\)

\(\Rightarrow3x=15^6:15^5\)

\(\Rightarrow3x=15\)

\(\Rightarrow x=\frac{15}{3}=5\)

Answer 2

a) (15x+2.2³)-4 = 10

15x+2.2³ = 10+4

15x+2.2³ = 14

=> 15x+2⁴=14

15x+16=14

15x=14-16

15x = -2

x = -2:15

x = -2/15

b) 3x.15⁵ = 15⁶

3x = 15⁶ : 15⁵

3x = 15¹

x = 15 : 3

x = 5

Answer 3

a) <=> 15x + 16 - 4 = 10

    <=> 15x             = -2

    <=>    x             = -2/15

b) <=> 3x = 15

    <=>  x = 5