Question

Giải phương trình

a)\(\sqrt{x^2-6x+9}=3\)

b)\(\sqrt{9x^2}=3-x\)

c)\(\sqrt{3-5x}=2\)

d)\(\sqrt{3x-7}=11\)

e_\(\sqrt{x-2}=-2\)

f)\(\sqrt{\frac{2x+7}{x+2}}=1\)

g)\(\frac{\sqrt{2x+7}}{\sqrt{x+2}}=1\)

Giúp mình với :< mình cần gấp ạ

Answer 1

Phần e) mình ghi nhầm ạ

e)\(\sqrt{x-2}=-2\)

Answer 2

a. \(\sqrt{x^2-6x+9}=3\)

\(\Leftrightarrow\sqrt{\left(x-3\right)^2}=3\)

\(\Leftrightarrow x-3=3\)

\(\Leftrightarrow x=6\)

Answer 3

b. \(\sqrt{9x^2}=3-x\)

\(\Leftrightarrow\sqrt{\left(3x\right)^2}=3-x\)

\(\Leftrightarrow3x+x=3\)

\(\Leftrightarrow4x=3\)

\(\Leftrightarrow x=\frac{3}{4}\)

Answer 4

c.\(\sqrt{3-5x}=2\)

\(\Leftrightarrow3-5x=4\)

\(\Leftrightarrow-5x=4-3\)

\(\Leftrightarrow5x=-1\)

\(\Leftrightarrow x=-\frac{1}{5}\)

Answer 5

c.(ghi lại đề)

\(\Leftrightarrow3x-7=121\)

\(\Leftrightarrow3x=121+7\)

\(\Leftrightarrow x=\frac{128}{3}\)

Answer 6

f. \(\sqrt{\frac{2x+7}{x+2}}=1\)

\(\Leftrightarrow\frac{2x+7}{x+2}=1\)

\(\Rightarrow2x+7=x+2\)

\(\Leftrightarrow2x-x=2-7\)

\(\Leftrightarrow x=-5\)

Answer 7

câu g tương tự câu f nhé !