Answer:
Can you please look at your question and tell me the whole thing. pls and ty :)
Step-by-step explanation:
Answer:
y=1; x=2
Step-by-step explanation:
Substitution:
x=2y
2x+5y=9
=> if x=2y, plug in the x value into other equation, so
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2(2y)+5y=9
4y+5y=9
9y=9
y=1
You have the Y value, so now solve for X
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plug in y value to x=2y
so x=2(1)
x=2
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.
m∠BCD= m∠ACB ÷ 2 = 134.76° ÷ 2 = 67.38°
Ok done. Thank to me :>