Answer:
A
Step-by-step explanation:
v - 2u
= < - 2, 4 > - 2 < 2.5, - 4 > ← multiply each component by 2
= < - 2, 4 > - < 5, - 8 > ← subtract corresponding components
= < - 2 - 5, 4 + 8 > = < - 7, 12 >
Graph A shows the resulting vector
Answer:
two real, unequal roots
Step-by-step explanation:
This is a quadratic equation. The quadratic formula can be used to determine how many and what kind of roots may exist:
Find the discriminant, which is defined as b^2 - 4ac, if ax^2 + bx + c = 0. In this case, a = 1, b = -2 and c = -8, so that the discriminant value is
(-2)^2 - 4(1)(-8), or 4 + 32 = 36.
Because the discriminant is real and positive, we know for certain that we have two real, unequal roots
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