Answer:
if this shape has greater that's obtuse
Y=-6/5x-7/5
You add it and move it to the other side
y+6/5x=-7/5
Multiply both sides by 5
5y+6x=-7
Rearrange
6x+5y=-7
He lost 8, so he is at -8, he then gains 15 so add 15 to -8"-8 + 15 = 7
He gains 7 so now add 7 to the total: 7+ 7 = 14
He then loses 4, so now subtract 4 from the total: 14 - 4 = 10
Answer: He gained 10 yards.
Answer:
x: work a woman can do in 1 day
y: work a girl can do in 1 day
Then
2x + 7y =1/4
4x + 4y =1/3
4x + 14y =2/4 (1)
4x + 4y =1/3 (2)
=> Let (1) - (2), 10y =2/4-1/3 <=>10y = 1/6 <=> y = 1/(6x10) = 1/60 (work)
=> From (2),4x = 1/3 - 4x1/60 => 4x = 16/60 => x = 4/60 (work)
=> 1 day, a woman and a girl can do: 1/60+4/60 = 5/60 =1/12 (work)
Then, the day required for a woman and a girl to complete work: 12 days