Answer:
cut the two lines at the corner, don't let the lines touch
Step-by-step explanation:
<span>X-Y=4,
X+Y=2
-------------add
2x = 6
x = 3
X - Y =4
3 - Y = 4
Y = 3 - 4
Y = -1
solution (3 , -1)</span>
Answer:
20 inches
Step-by-step explanation:
If that's centimeters on the x-axis and inches in the y-axis, then the slope is 2/5 and the y-intercept is 0.

The slope of 2/5 in this context means 2 inches per 5 centimeters. Then, either by solving the equation or by graphing the line, you can determine that there are about 20 inches in 50 centimeters.
Answer:
Step-by-step explanation:
Don't use 0 as a substitute for θ. 0 is always 0.
cosθ = -5/(2√15)
secθ = 1/cosθ = -2√15/5