Question

Câu 1: Tìm x, biết:

a)\(x^2-\dfrac{16}{25}=0\)                                    b)\(\dfrac{2}{5}-\left|\dfrac{1}{2}-x\right|=6\)

C2.Tính giá của biểu thức: 

a)\(A=1\dfrac{5}{13}-0,25-\left(2\dfrac{5}{9}+\dfrac{18}{13}-\dfrac{1}{4}\right)\)

b)\(\dfrac{\dfrac{3}{5}.7^2-3.5^6+\dfrac{3}{5}.3^9}{\dfrac{3}{4}.7^2-\dfrac{3}{4}.5^7+\dfrac{3}{4}.3^9}\)

 

 

 

Answer 1

a)

x^2-16/25=0

x^2-4^2/5^2=0

=>x-4/5=0

x=0+4/5

 

x=0/5