Let the base be b. Then the height is b-4. So:
1/2(b)(b-4)=6
b²-4b-12=0
(b-6)(b+2)=0
b=6
b-4=2
☺☺☺☺
Answer:
In bold answers with correct units
3) 6 x 3 = 18 + 1/2 x 12 x 15 = 90 = 90+ 18 = 108ft^2
4) = 12 x 12 = 144 + 4x4 = 16 +12 x 4 = 48 = 144+12+48 = 204m^2
5) = 8 x 12 = 96 + 1/2 x 4 x 6 = 12 = 108ft^2
6) = 3x 3 = 9 + pi3^2 = 28.2743339 (x2) =56.5486678 + 9 = 65.5m^2
proves 4 semi circles = 2 circles
7) 10 x 8 = 80 +4 x 4 = 16 + 1/2 x 2 x 4 = 4 = 20+80= 100ft^2
proves 14-8-4 = 2ft is the triangle length and 10-6 = 4 the triangle height.
8) 4x6 = 24 + 1/2 x 4 x 2 = 4 + pi 4^2 = 1/2 x 50.2654825 = 24+4 + 25.1329 = 53.1m^2
This is the concept of algebra, let the width be x
height=x-4
length=2x+10
the volume of the box is:
volume=length*width*height
=x(x-4)(2x+10)
expanding the above we get:
(x^2-4x)(2x+10)
=x^2(2x+10)-4x(2x+10)
=2x^3+2x^2-40x=264
solving the above we get real solution will be
x=6
thus we conclude that the width is x=6 inches
length=2*6+10=22 inches
height=x-4=6-4=2 inches
thus the dimension will be:
width=6 inches, length=22 inches, height=2 inches
I do not understand why you or your teacher have written down a certain number of minutes by each equation, but I will do my best to answer your question. I hope that I’m able to help.
1,2) 20 + 3.5x = 30 + 2.75x
-20 -20
3.5x = 30 + 2.75x - 20
-2.75x -2.75x
0.75x = 10
/0.75 /0.75
x = 13.333...
3,4) 3.5x + 2.75x = 20 + 30
6.25x = 50
/6.25. /6.25
x = 8
Answer:
5 1/2 is your second answer :)