Answer:
Step-by-step explanation:
<u>x is side of right triangle with other sides:</u>
<u>Then x is:</u>
- x² = √20² - 4²
- x² = 4
- x = 2
Hello!
There are 1000 meters in a kilometer
Multiply 45km by 1000
45 * 1000 = 45000 cubic meters
The answer is 45,000 cubic meters
Hope this helps!
Check the picture below.
since in a rhombus the diagonals bisect each other, thus EC = EA.
now, the rhombus is simply 4 congruent triangles, we know the base and height of one of them, thus
![\bf \textit{area of a triangle}\\\\ A=\cfrac{1}{2}bh~~ \begin{cases} b=8\\ h=15 \end{cases}\implies A=\cfrac{1}{2}(8)(15)\implies A=60 \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{area of all 4 triangles}}{4(60)\implies 240}](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Barea%20of%20a%20triangle%7D%5C%5C%5C%5C%20A%3D%5Ccfrac%7B1%7D%7B2%7Dbh~~%20%5Cbegin%7Bcases%7D%20b%3D8%5C%5C%20h%3D15%20%5Cend%7Bcases%7D%5Cimplies%20A%3D%5Ccfrac%7B1%7D%7B2%7D%288%29%2815%29%5Cimplies%20A%3D60%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Barea%20of%20all%204%20triangles%7D%7D%7B4%2860%29%5Cimplies%20240%7D)
2(x+7) + x=20
(2)(x) + (2)(7) + x=20 Distribute
2x+14 + x =20
(2x+x) + (14) =20 Combine Like Terms
3x+14=20
- 14 -14 Subtract 14 from both sides
3x = 6
3x/3 6/3 Divide Both Sides by 3
x = 2
Let me know if you still don't understand
If Sandra mixes <em>x</em> L of 65% solution with <em>y</em> L of 90% solution, then the resulting mixture has a total volume of
<em>x</em> + <em>y</em> = 500
litres, and it contains
0.65<em>x</em> + 0.90<em>y</em> = 0.75 (500) = 375
litres of alcohol.
Solve the first equation for <em>y</em> :
<em>y</em> = 500 - <em>x</em>
<em />
Substitute this into the second equation and solve for <em>x</em> :
0.65<em>x</em> + 0.90 (500 - <em>x</em>) = 375
0.65<em>x</em> + 450 - 0.90<em>x</em> = 375
75 = 0.25<em>x</em>
<em>x</em> = 300
Solve for <em>y</em> :
<em>y</em> = 500 - 300
<em>y</em> = 200
So, Sandra should mix 300 L of 65% solution with 200 L of 90% solution.
