**Answer:**

length=8 , wide=5

**Step-by-step explanation:**

Let length=x and wide=y

convert the question into two equations

3+y=x .......1

xy=40 .......2

so we need to substitute x into y or y into x

x=3+y ,

(3+y)y=40

y²+3y=40

y²+3y-40=0

from that use calculator or manually factorise it

(y+8)(y-5)=0

y= –8 , y=5

we need to choose positive answer so y=5

then find for x

5x=40

x=8

**Answer:**

The 98% confidence interval is (546.586 ,758.614).

**Step-by-step explanation:**

We are** given the following** in the question:

Sample size, n = 50

Sample mean = 652.6 vehicles per hour

Sample standard deviation = 311.7 vehicles per hour

**98% confidence interval:**

Putting the values, we get,

**The 98% confidence interval is (546.586 ,758.614).**

Sin (a+b) = sin a. cos b + cos a. sin b

a= 50° and b=40°, then

sin(50+40) = sin 50° . cos 40° + cos 50° . sin 40°

sin(50+40) = sin 90° = 1 and

sin 50° . cos 40° + cos 50° . sin 40° = 1

To get the answer we can use proportion

86 --------------45%

x ---------------- 100%

Now cross multiply

x*45%=86*100

45x=8600 /:45 (divide both sides by 45)

x=191.11 - its the answer

**Answer: -3**

**Step-by-step explanation:**