Answer:
35
Step-by-step explanation:
2x+1=71
71-1=70
70÷2=35
therefore x must be 35
Sadly, I can't see the picture you're looking at as you make that statement.
But I'm pretty sure that when you combine an exterior angle with the interior
angle adjacent to it, you'll wind up with 180°, because they form a linear line.
There actually isn't any such thing as a linear plane.
It depends on which variable is eliminated.
If you multiply the second equation by -1 and eliminate the y:
3x - y = 7
-6x + y = -10
-3x = -3 or x = 1
If you multiply the first equation by -2 and eliminate the x:
-6x + 2y = -14
6x - y = 10
y = -4
Consider the suggested option:
1) if in 20 gr. of 50% solution given, then pure salt in this mix is 0.5*20=10 gr., and pure water is 0.5*20=10 gr.
2) after Maya added 5 gr. pure salt is 10+5=15 gr. Total mass of mix is 15(pure salt)+10(pure water)=25 gr.
3) new solution is 15/25=0.6 or 60%.
Answer: 25 gr. of 60% salt solution.
