GIÚP JMK VỚI:
\(E=5\sqrt{16}-4\sqrt{9}+\sqrt{25}-0,3\sqrt{400}\)
NHANH HỘ MK NHA. THANKS
E = \(5\sqrt{16}-4\sqrt{9}+\sqrt{25}-0,3\sqrt{400}\)
\(E=5.4-4.3+5-0,3.20=20-12+5-6=7\)
5\(\sqrt{16}\)-4\(\sqrt{9}\)+\(\sqrt{25}\)-0,3\(\sqrt{400}\)
\(5\sqrt{16}-4\sqrt{9}+\sqrt{25}-0,3\sqrt{400}\)
\(5\sqrt{16}-4\sqrt{9}-\sqrt{25}-0,3\sqrt{400}\)
\(=5.4-4.3+5-0,3.20\)
\(=20-12+5-6\)
\(=7\)
\(5\sqrt{16}-4\sqrt{9}+\sqrt{25}-0,3\sqrt{400}\)
\(5.\sqrt{16}-4.\sqrt{9}+\sqrt{25}-0,3.\sqrt{400}\)
\(=5.4-4.3+5-\frac{3}{10}.20\)
\(=20-12+5-6\)
\(=8+5-6\)
\(=13-6\)
\(=7\)
=5*4-4*3+5-0.3*20
=20-12+5-6
=8+5-6
=13-6
=7
tính: \(5\sqrt{16}-4\sqrt{9}+\sqrt{25}-0,3\sqrt{400}\)
Ta có : \(5\sqrt{16}-4\sqrt{9}+\sqrt{25}\)-0,3\(\sqrt{400}\)
= 5.4 - 4.3 + 5 - 0,3.20
= 20-12+5-6
= 9
2) giải pt
a) \(\sqrt{4-2x}=5\)
b) \(\sqrt{25\left(x+1\right)}+\sqrt{9x+9}=16\)
c) \(\sqrt{4x^2+12x+9}=4\)
giúp mk vs ạ mk cần gấp
a) ĐKXĐ: x <= 2
pt --> 4 - 2x = 25 <=> x = -21/2 (thỏa)
b) ĐKXĐ: x >= -1
pt <=> 8sqrt(x + 1)=16 <=> sqrt(x+1)=2 --> x + 1 = 4 <=> x = 3
(2) giải pt:
a) \(\sqrt{4-2x}=5\)
b) \(\sqrt{25\left(x+1\right)}+\sqrt{9x+9}=16\)
\(\sqrt{4x^2+12x+9}=4\)
giúp mk vs ạ mai mk hc rồi
a, ĐKXĐ: \(x\le2\)
\(\sqrt{4-2x}=5\\ \Leftrightarrow4-2x=25\\ \Leftrightarrow2x=-21\\ \Leftrightarrow x=-10,5\left(tm\right)\)
b, ĐKXĐ: \(x\ge-1\)
\(\sqrt{25\left(x+1\right)}+\sqrt{9x+9}=16\\ \Leftrightarrow5\sqrt{x+1}+\sqrt{9\left(x+1\right)}=16\\ \Leftrightarrow5\sqrt{x+1}+3\sqrt{x+1}=16\\ \Leftrightarrow8\sqrt{x+1}=16\\ \Leftrightarrow\sqrt{x+1}=2\\ \Leftrightarrow x+1=4\\ \Leftrightarrow x=3\)
c, \(\sqrt{4x^2+12x+9}=4\Leftrightarrow4x^2+12x+9=16\\ \Leftrightarrow4x^2+12x-7=0\\ \Leftrightarrow\left(4x^2-2x\right)+\left(14x-7\right)=0\\ \Leftrightarrow2x\left(2x-1\right)+7\left(2x-1\right)=0\\ \Leftrightarrow\left(2x-1\right)\left(2x+7\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=-\dfrac{7}{2}\end{matrix}\right.\)
a: \(\Leftrightarrow4-2x=25\)
hay \(x=-\dfrac{21}{2}\)
c: \(\Leftrightarrow\left|2x+3\right|=4\)
\(\Leftrightarrow\left[{}\begin{matrix}2x+3=4\\2x+3=-4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=-\dfrac{7}{2}\end{matrix}\right.\)
\(5\sqrt{16}-4\sqrt{9}+\sqrt{25}-\sqrt{400}\)
\(5\sqrt{16}-4\sqrt{9}+\sqrt{25}-\sqrt{400}\)
\(=5.4-4.3+5-20\)
\(=20-12+5-20\)
\(=-7\)
5√16−4√9+√25−√400
=5.4−4.3+5−20
=20−12+5−20
=8+5-20
=13-20
=-7
Bài 4: Cho\(\dfrac{25+x}{9}\) = \(\dfrac{51-y}{16}\) = \(\dfrac{70+z}{25}\) với\(\sqrt{9}\) . y3 -\(\sqrt{16}\) = 7.\(\sqrt{121}\)
Tính x + y + z
Help me! Thanks a lot!