Answer: The answer is 8.
Step-by-step explanation: The first step is to convert the expression into figures. We shall call the unknown number Y. So if we are told “the square of a number,” that means Y squared, or better still, Y^2. Further we are told “the difference between the square of a number and 40” and that can be written as;
Y^2 - 40.
Next we are told that this expression is equal to 3 times that number (that is 3Y). That can now be written out as follows,
Y^2 - 40 = 3Y
If we move all expressions to one side of the equation, what we would have is,
Y^2 - 3Y -40 = 0
(Remember that when a positive value crosses to the other side of an equation it becomes negative and vice versa)
We now have a quadratic equation
Y^2 -3Y - 40 = 0
By factorizing we now have
(Y -8) (Y + 5) = 0
Therefore Y - 8 = 0 or
Y + 5 = 0
Hence, Y = 8 or Y = -5
Since we are asked to calculate the positive solution, Y = 8
The number of pages the student can read in a minute is an illustration of rates.
The time left to complete the whole book is 90 minutes
From the complete question, the student's rate is:
The number of pages is:
First, we calculate the time to read the whole book
The number of the student has read is:
Next, we calculate the time spent on the 25 pages
Convert to minutes
So, the time left is:
This gives
Convert to minutes
Hence, the time left is 90 minutes
Read more about rates at:
brainly.com/question/18065083
Answer: y=4x-4
Step-by-step explanation:
To find the equation fo the line parallel to the given line, we can use the given point to find the y-intercept. We know that the slope must stay the same because parallel lines NEVER touch or cross. This means that the slope MUST be the same.
y=4x+b
We can use the given point to find the y-intercept.
8=4(3)+b [multiply]
8=12+b [subtract both sides by 12]
b=-4
Now that we have found the y-intercept, we can complete the equation.
y=4x-4
Answer:
Let x = # of hot dogs sold
Let x + 31 = # of sodas sold
For the total, do: x + x + 31 = 173
2x + 31 = 173
-31 -31
2x = 142
Divide out both sides by 2; to get: x - 71
That gives us 71 hot dogs; and 71 + 31 = 102 sodas
To test this: 71 + 71 + 31 = 173
173 = 173 [Check]
Step-by-step explanation:
its above up there
Answer:
x > 
Step-by-step explanation:
given
2x > 7 ( isolate x by dividing both sides by 2 )
x >
