<h3>
Answer: 41 cm^2</h3>
Explanation:
Form a horizontal line as shown below (see attached image). This forms 2 separate smaller rectangles
- The bottom rectangle has area of 4*8 = 32 cm^2
- The top rectangle has area of 3*3 = 9 cm^2
The total area is therefore 32+9 = 41 cm^2
You can say "square cm" or "sq cm" in place of the "cm^2".
2x - 3y = -24
x+ 6y = 18
you solve the first one by the x:
2x = -24 + 3y
x = (-24+3y)/2
then you substitute what you found in the other equation and you solve by y
(-24+3y)/2 + 6y = 18 multiply everything by 2
-24 + 3y + 12y = 36
3y + 12y = 36 + 24
15y = 60
y = 60/15
y = 4
Good job! You found your y! :D
Now let's substitute the y in the first equation with 4:
2x - 3(4) = -24
2x - 12 = -24
2x = -24 + 12
2x = -12
x = -12/2
x= -6
Done!! ;) <span />
Slope-intercept form:
y=mx+b
m=slope
b=y-intercept
Data of the first line:
m=-5
b=y-intercept=3 (y-intercept=it is the value of "y" when x=0)
y=-5x+3
A line perpendicular to the line y=mx+b will have the following slope:
m`=-1/m
Therefore: the line perpendicular to the line y=-5x+3 will have the following slope:
m´=-1/(-5)=1/5
Point-slope form of a line: we need a point (x₀,y₀) and the slope (m):
y-y₀=m(x-x₀)
We know, the slope (m=1/5) and we have a point (3,2) therefore:
y-y₀=m(x-x₀)
y-2=1/5(x-3) (point-slope form)
y-2=(1/5)x-3/5
y=(1/5)x-3/5+2
y=(1/5)x+7/5 (slope-intercept form)
Answer: the line perpendicular to the first line will be: y=(1/5)x+7/5
