Answer:
x < 9
Step-by-step explanation:
subtract 7 from both sides of the inequality
- 4x > - 36 ( divide both sides by - 4 )
When multiplying/dividing by a negative quantity the symbol is reversed
x < 9 ← note reversal of symbol
(f+g)(x) just means f(x) + g(x)

Choice B
Answer:
16/25
Step-by-step explanation:
length of screen B=44*(5/4)=55cm
and its width=32*(5/4)=40cm
so, screen B had dimensions 55cm by 40 cm
screen A area=44*32 cm sqr
screen B area=55*40 cm sqr
so, model A screen area/model B screen area
=(44*32)/(55*40)
=16/25
Answer: Running speed is 10k/h
Biking speed is 50k/h
Step-by-step explanation:
My procedure may be unconventional, but it works:
Compute the time it takes, then translate to speed. 25k at biking speed takes 2 hours less than at running speed which is 1/5 bike speed.
Distance/speed = time 25/x=25/(5x-2) cross multiply divisors
25(5x-2) = 25x ==> 125x -50 =25x ==> 100x = 50
x = 0.5 hours at biking speed 25k/0.5h = 50k/h
Running speed = 50/5 10k/h
Proof: 25k/ 10k/h = 2.5 hours
25k /50k/h = 0.5 hours
2.5 h - .5 h = 2 hours, the difference stated in the question.