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Question
find the value of y when x=7 in the equation y=3x2-8x
Questioner: myra
Country: United States
Category: Advanced Math
Private: No
Subject: equation
Question: find the value of y when x=7 in the equation y=3x2-8x
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Hi, Myra,
Use substitution, and use it this way:
y = 3x^2 - 8x << original.
y = 3()^2 - 8() << substitute () for x.
y = 3(7)^2 - 8(7) << insert
y = 3(49) - 56 << do the arithmetic.
You can finish up.
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Paul Klarreich
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I can answer questions in basic to advanced algebra (theory of equations, complex numbers), precalculus (functions, graphs, exponential, logarithmic, and trigonometric functions and identities), basic probability, and finite mathematics, including mathematical induction. I can also try (but not guarantee) to answer questions on Abstract Algebra -- groups, rings, etc. and Analysis -- sequences, limits, continuity. I won't understand specialized engineering or business jargon.
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I taught at a two-year college for 25 years, including all subjects from algebra to third-semester calculus.
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