It's important that you use the correct symbol to indicate exponentiation.
<span>f(x) = 0.4(3)x f(x) = 3(0.5)x f(x) = 0.8(0.9)x f(x) = 0.9(5)−x should be written as:
</span><span>f(x) = 0.4(3)^x f(x) = 3(0.5)^x f(x) = 0.8(0.9)^x f(x) = 0.9(5)−x.
Please double-check that last problem, as I am unsure of whether you meant 0.9^5 or (0.9)(5).
f(x) = 0.4(3)^x is definitely an exponential function.
Please try again. Do those problems that you can do an ask questions about the others.
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bearing in mind that
standard form for a linear equation means
• all coefficients must be integers, no fractions
• only the constant on the right-hand-side
• all variables on the left-hand-side, sorted
• "x" must not have a negative coefficient
8 - 5y = - 2x
2x - 5y = - 8
It is B because tangent lines are always perpendicular to radii