Answer:
Step-by-step explanation:
Total marbles in bag= 55
Given that
The number of green marbles is 7 more than 5 times the number of blue marbles.
Let green marble be x
And blue marble be y
Therefore,
Green=seven more than 5 times blue
Green=7+5timesblue
x=7+5y. Equation 1
Also the sum of the marbles is 55
x+y=55. Equation 2
Substitute equation 1 into 2
7+5y+y=55
7+6y=55
6y=55-7
6y=48
y=48/6
y=8
From equation 2
x+y=55
Then, x=55-y
x=55-8
x=47
Then, green marbles is 47.
Also, Blue marbles is 8
I wonder what the best way of explaining this is? You could graph the results for each choice. Or you could reason it out.
The first thing you have to do it deal with y = 3. Draw a really crude graph like a set of axis. Make the y values go from -5 to + 5. x for the moment does not matter.
Draw a horizontal line through y = 3 or going through the point (0,3). Now here's the catch and you're going to have to read it very carefully.
Condition One
If a>0 then the graph opens upward and b is going to have to be less than 3. That sentence is an absolute nightmare. Think carefully about what a>0 means. Make it 2 and draw a rough graph opening upward on the crude axis you have drawn. b is the y value of the minimum, so that minimum has to be less than 3. Are there any point like that? The two points where a>0 are C and D.
C
The lowest point that C will hit is 4. That's not good enough. b = 4 is the lowest y value. C is not the answer
D
The lowest point is 3. The graph will just touch y = 3. That's not good enough either. Touching y = 3 does not produce 2 roots. It produces just one.
Condition Two
a < 0 Here the graph opens downward. It means the a<0 and b>3. You need to look at A or B. Which point does that? A has a maximum below 3. It's no good. A is wrong.
So the answer must be B. a<0 and b>3. Right on 2 solutions.
Answer:
0.8 OR 
Step-by-step explanation:
The reciprocal of any number is the number that it multiplies by to equal 1.
The reciprocal can be found by simply converting the number into a fraction and then 'flipping' the fraction as any number multiplied by its reciprocal is 1.
E.g.
No. X/Y * Y/X (its reciprocal) = 1
So, to find the reciprocal of 1.25,we should first convert 1.25 to a fraction.
1.25 = 125/100
Now we just flip 5/4 to get our reciprocal:
= 0.8
Test: 0.8 * 1.25 = 1
The reciprocal of 1.25 (
) is 0.8 ().
Hope this helped!
ANSWER: 40
EXPLANATION : because if u reduce 55 with 15 is 40
Answer:
a) 2x² - x + 3 = x(2x + 1) - 2x
<=> 2x² - x + 3 = 2x² + x - 2x
<=> 3 - x = - x
<=> 3 = 0
=> no solution
b) x/2 - x/3 - x/4 = 1/12
=> the euqation has the solution x = 1
c) |x - 5| = 2|x|
=> x - 5 = 2x
or x - 5 = -2x
<=> x = -5
or 3x = 5
<=> x = -5
x = -5or x = 5/3
d) defined conditions: 2 - x 》 0
<=> x 《 2
we have:
<=> x = 0 (because x 《 2)
e)
<=> x = -1/4
