Answer:
21.5 or 26.8
Step-by-step explanation:
a car with a 18 gallon gas tank can average 21.5 miles per gallon when driven in the stop and go traffic of the city and 26.8 miles per gallon when driven on the highway
You labeled the triangle wrong sides 'a' and 'b' are supposed to be the sides that make the right angle. the other side is called the hypotenuse which is the longest side which you should have labeled 'c'
so Pythagorean theorem says
a^2+b^2=c^2
so
(2x+1)^2+(11x+5)^2=(12x+1)^2
distribute
(4x^2+4x+1)+(121x^2+110x+25)=(144x^2+24x+1)
add like terms
125x^2+114x+26=144x^2+24x+1
subtract 125x^2 from both sides
114x+26=19x^2+24x+1
subtract 114x from both sides
26=19x^2-90x+1
subtract 26 from both sides
0=19x^2-90-25
factor
(x-5)(19x+5)=0
therefor x-5=0 and/or 19x+5=0
so
x-5=0 add 5 to both sides
x=5
19x+5=0
subtract 5 from both sides
19x=-5
divide both sides by 19
x=-5/19
since side legnths can't be negative, we can cross this solution out
so x=5
subtitute
1+2x
1+2(5)
1+10=11
side a=11
11x+5
11(5)+5
55+5=60
side b=60
12x+1
12(5)+1
60+1=60
side c=61
add them all up
side a+b+c=11+60+61=132=total legnth
Answer:
3rd
Step-by-step explanation:
If you know about linear eq. it's just a simple rule no worry
18. The perimeter is simply √3 + √3 + √3 + √3 or 4√3cm, since the perimeter is just all sides added together. You could add the decimal numbers together using a calculator, which I'm not sure if you're supposed to do in your class.
The area is just width times length, so √3 • √3 = 3cm².
19. The perimeter is 2√5 + 2(9 - √5).
This can also be written as 2√5 + 18 - 2√5, which leaves you with a perimeter of 18ft.
The area would be √5 • (9 - √5), which leaves you with (9√5 - 5)ft².
20. The formula for the perimeter (or circumference) of a circle is π times the diameter of the circle. Using the radius of the circle, 1/π, the diameter is 2/π, so
π • 2/π = 2. The circumference of the circle is 2 inches.
The area of the circle is calculated with the equation πr², so
π(1/π)² = π • 1/(π²) = π/(π²) = π. The area is simply π in².
12 ) 18
13) 54
14) 28/54 (8weeks x 7 days) = 1/2
18/24 = 3/4
therefore rates not equal
15) 0 and 0 ;1 and 4; 2 and 8;3 and 12