9514 1404 393
Answer:
x = 7
Step-by-step explanation:
The equation can be rewritten to ...
8x = 13n +4 . . . . for some integers x and n
x = (13n +4)/8
For x to be an integer, 13n must be an odd multiple of 4. Since 13 is an odd number, n=4 will do.
x = (13·4 +4)/8 = 56/8
x = 7
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The graph shows a "trial and error" method of solution. Only values of x less than 13 need to be examined.
A. 2x^2 - 3x + 10 = 2x + 21
2x^2 - 3x - 2x + 10 - 21 = 0
2x^2 - 5x - 11 = 0 (quadratic equation)
2x^2 - 6x - 7 = 2x^2
2x^2 - 2x^2 - 6x - 7 = 0
-6x - 7 = 0 (not a quadratic equation)
5x^2 + 2x - 4 = 2x^2
5x^2 - 2x^2 + 2x - 4 = 0
3x^2 + 2x - 4 (quadratic equation)
5x^3 - 3x + 10 = 2x^2
5x^3 - 2x^2 - 3x + 10 = 0 (not a quadratic equation)
Therefore, options a and c can be solved using the quadratic formula.
Answer:
80%
Step-by-step explanation:
28/35 = 0.8
Divide. Convert a decimal to a percent by multiplying times 100.
0.8 × 100 = 80
Tara earned an 80%
You could use a calculator as described above or using mental math or pencil and paper:
28/35 = 4/5
Simplify.
4/5 = 8/10 = 80/100
Percent means per hundred, change 28/35 to hundredths as above.
Tara (still) gets an 80%.
