The second equation is <span>-5-2y=2, then
</span>
<span>-2y=2-(-5),
</span>
-2y=2+5,
-2y=7,
y=7÷(-2),
y=-3.5.
The first equation is 2x+5y=16, subtitude y=-3.5 in this equation, then
2x+5·(-3.5)=16,
2x-17.5=16,
2x=16-(-17.5),
2x=16+17.5,
2x=33.5,
x=33.5÷2,
x=16.75.
Answer: (16.75,-3.5)
3 yrs ago:
Alice - x
Jane - 3x
Fast forward 2 years... 1 year ago:
Sum of their ages = 62
Equation to solve: x + 3x = 62
4x = 62
----- -----
4 4
x = 15.5
From this, we can deterime that Alice is 15 1/2 years old.
Then, plug in 15.5 for x in 3x to find Jane's age.
15.5 × 3 = 46.5
From this, we can determine that Jane is 46 1/2 years old.
I hope this helps you to understand this problem better.
In which place? Of the value one tens hunderd thousnd