Answer:
<h3> 26²/₃ liters of 15% acid and 13¹/₃ liters of 33% acid</h3>
Step-by-step explanation:
Concentration Amount of Amount
of Solution Solution (L) of Acid
15% x 0.15x
33% y 0.33y
21% 40 0.21•40
x + y = 40 ⇒ x = 40 - y
0.15x + 0.33y = 0.21•40
0.15(40 - y) + 0.33y = 0.21•40
6 - 0.15y + 0.33y = 8.4
0.18y = 2.4
y = 13¹/₃
x = 40 - 13¹/₃ = 26²/₃
Check picture below, solve for "x" and "y"
unless you've already covered the 30-60-90 triangle, then check your book on them, to see the ratios, using the 30-60-90 ratios is simpler
Answer:
Equation of circle in standard form with centre (0, – 10) and radius 6. 
Step-by-step explanation:
We need to write equation of circle in standard form with centre (0, – 10) and radius 6.
The equation of circle is: 
where (h,k) is centre of circle and r is radius
We are given centre (0,-10) so, h=0, k=-10 and radius r = 6
Putting values and finding equation:

So, equation of circle in standard form with centre (0, – 10) and radius 6. 
The second shape is double the first so you would do AB = 2 and then times by 2 as its double and you will get 4
answer = 4
Answer:
Step-by-step explanation:
the current ages:
father= 32 yrs old
son=5 yrs old
-------
4(5+x) = 32+x
20+4x = 32+x
4x-x = 32–20
3x =12
x = 12/3
x = 4 years
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after the 4 years later the farther age will be 36 ( 32+4 = 36)
the son will be 9 ( 5+4= 9 years)
the x presents how the father will be after 4 times the age of the son