Part A: the radicand is the same as the discriminant, therefore is b2 - 4ac
In 9x^2 - 16x + 60 = 0, a = 9, b = -16, c = 60
so b2 - 4ac =

Part B: Solve 4x^2 + 8x - 5 = 0
What would make 8? (5×2)-2 = 8, so:
(2x+5)(2x-1) = 0
2x+5 = 0
2x = -5
x = -5/2
2x-1 = 0
2x = 1
x = +1/2
So the solutions are: -5/2, +1/2
Answer: speed of the car is 88 miles per hour
the speed of the motorcycle is 78 miles per hour
Step-by-step explanation:
Number of miles travelled by car = 312
Number of miles travelled by motorcycle = 272
Let x = speed of the car
Let y = speed of the motorcycle
If the car's speed is 10mph more than the motorcycle's, it means
x = y + 10 - - -- - - 1
Time taken for car to travel 312 miles is distance /speed = 312/x
Time taken for motorcycle to travel 272 miles is distance /speed = 272/y
The car travels 312 miles in the same time that a motorcycle traveled 272.
This means
312/x = 272/y
312y = 272x
y = 272x/312
Substituting y = 272x/312 into equation 1, it becomes
x = 272x/312 + 10
312x = 272x + 3120
312x-272x = 3120
40x = 3120
x = 3120/40 = 78 miles per hour
x = y + 10 = y + 78
x = 88 miles per hour
Taxi A
1mile £3.50+£1.75=£5.25
Taxi B
1mile £1.25+£2.00=£3.25
Taxi A
2miles £3.50+£3.50=£7.00
Taxi B
2miles £1.25+£4.00=£5.25
Taxi A
3miles £3.50+£5.25=£8.75
Taxi B
3miles £1.25+£6.00=£7.25
Taxi A
4miles £3.50+£7.00=£10.50
Taxi B
4miles £1.25+£8.00=£9.25
Taxi A
5miles £3.50+£8.75=£12.25
Taxi B
5miles £1.25+£10.00=£11.25
Taxi A
6miles £3.50+£10.50=£14.00
Taxi B
6miles £1.25+£12.00=£13.25
Taxi A
7miles £3.50+£12.25=£15.75
Taxi B
7miles £1.25+£14.00=£15.25
Taxi A
8miles £3.50+£14.00=£17.50
Taxi B
8miles £1.25+£16.00=£17.25
Taxi A
9miles £3.50+£15.75=£19.25 (the same)
Taxi B
9miles £1.25+£18.00=£19.25 (the same)
^^^
They would have to drive 9 miles for the taxi to cost the same.
Hope this helped, this is the longest way to work it out but also the simplest.
Answer:
Im not sure but i think 2 is the answer
Step-by-step explanation: