(12x + 9y) + (-2y) - (4x - 3y)
= 12x + 9y - 2y - 4x + 3y
= 12x - 4x + 9y - 2y + 3y
= 8x + 10y
A) 8x + 10y
Let's call the width: w
the lenght is then 3w+4 ("4 more than 3 times the width")
and the parameter would be 2(w+3w+4), that is 2*(4w+4), that is 8w+8.
this is also equal to 18.4:
8w+8=18.4
8w=10.4
w=1.3
this is the width, and the lenght is:
4+3*1,3=4+3.9=7.9
and the area is their product:
1.3*7.9=10.27
X is the base of the exponent.
Based on your problem, you only have one given. So, you can't make an equation for this because there are not limits to the equation. The only thing that you know is that the three numbers are consecutive even integers. My way of solution for this is trial-and-error. However, it's really quite easy.
For example: 42 + 46 = 88. I have to increase the numbers more to reach 136. Suppose: 82 + 86 = 168. That exceeded 136. So, it must be between 46 and 82. Suppose again: 66 + 70 = 136. Therefore, the sequence of the consecutive even integers are 66, 68, and 70.
Joe runs one lap around a track in 80 seconds. Joe and Jim meet after 30 seconds.We know how long does it take for Joe to run one lap, so we can calculate what distance he runs in 30 seconds:
He runs half lap for 40 seconds. He runs quarter lap for 20 minutes and he runs 1/8 lap for ten minutes. So for 30 seconds he runs 3 * 1/8 lap=3/8 lap.
Because Jim runs in opposite direction this means that he will meat with Joe at 1-3/8=5/8 lap. So, Jim runs 5/8 lap for 30 seconds.
1/8 lap Jim runs for 30/5=6 seconds, so Jim needs 8*6=48 seconds to run the lap.
After 30 seconds Joe has run e runs
