a is given to us so just plug a into the first equation:
b-3 - 3b =9
Add 3 to both sides:
b-3b=12
Combine like terms:
-2b=12
Divide by -2 to get b by itself:
b=-6
The only answer with b as -6 is the first one, (-9,-6)
Answer:
I think it would be 9 miles.
<span>Distance is equal to rate times time, and time is the unknown in this instance. To find time, divide distance by rate. In this case, Joe wants to use a rate five miles per hour less than his planned speed of 75 miles per hour, which is 70. Dividing 310 miles by 70 miles per hour yields an expected travel time of 4.4 hours.</span>
Answer:
area (A) =(9x+108)unit^2
perimeter (P) =(2x+42) units
Step-by-step explanation:
area(A) =length(l) × breadth(b)
perimeter(P) =2(l+ b) {which is sum of all sides}
so, l = 7+x+5 = (x+12) units and b = 9 units
now, A=(x+12) × 9 units^2
=(9×x + 12×9 ) units^2
Therefore,
A =(9x+108)unit^2
next, P=2{(x+12)+9}
=2(x+21)
Hence,
P=(2x+42) units
