How many x-intercepts does the graph of y = 2x^2 – 8x + 5 have?
2 answers:
A graph of the equation shows the appropriate choice to be
C. 2
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If you would rather, you can look at the value of the discriminant. For the equation y = ax²+bx+c, the discriminant (d) is
d = b²-4ac
For your equation, this evaluates to
d = (-8)²-4(2)(5) = 64 -40 = 24
When the discriminant is positive, the function has two real roots (2 x-intercepts). When it is zero, there is only one x-intercept, and when it is negative, there are none (the roots are complex).
C. 2
_____
If you would rather, you can look at the value of the discriminant. For the equation y = ax²+bx+c, the discriminant (d) is
d = b²-4ac
For your equation, this evaluates to
d = (-8)²-4(2)(5) = 64 -40 = 24
When the discriminant is positive, the function has two real roots (2 x-intercepts). When it is zero, there is only one x-intercept, and when it is negative, there are none (the roots are complex).
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Answer:
Four less than an unknown value E)
Quotient of a variable and four B)
Some number to the power of four A)
Four times an unknown value D)
Four more than some number C)
Step-by-step explanation:
Let's analyze each statement separately:
- Four less than an unknown value --> this means that we have to subtract 4 to an unknown value. Calling the unknown value, it means we have to write
- Quotient of a variable and four --> this means we have to divide a variable by 4. Calling the unknown variabl, it means we have to write
- Some number to the power of four --> this means that we have to write the power of a number, in the form , where m in this case is equal to 4. Calling
the unknown number, it means we have to write
- Four times an unknown value --> this means that we have to multiply an unknown value by 4. Calling our unknown values, we have to write
- Four more than some number --> this means we have to add 4 to an unknown number. Calling the unknown number, it means we have to write