Q. Solve the exponential equation for x.28x−4⋅163x−5=169x+2x=□
Recognize Power of 2: Recognize that 16 is a power of 2, specifically 16=24. This will allow us to rewrite the equation in terms of the same base.
Rewrite Exponents: Rewrite 163x−5 and 169x+2 as (24)3x−5 and (24)9x+2 respectively, using the property abc=(ab)c.
Simplify Exponents: Simplify the exponents on the right side of the equation by multiplying them out: (24)(3x−5)=2(4∗(3x−5)) and (24)(9x+2)=2(4∗(9x+2)).
Rewrite Equation: Now rewrite the equation with these simplifications: 28x−4×24×(3x−5)=24×(9x+2).
Add Exponents: Add the exponents on the left side of the equation using the property am⋅an=am+n: 28x−4⋅212x−20=28x−4+12x−20.
Combine Like Terms: Simplify the exponent on the left side by combining like terms: 28x−4+12x−20=220x−24.
Set Exponents Equal: Now we have 220x−24=236x+8. Since the bases are the same and the exponents must be equal for the equation to hold, we can set the exponents equal to each other: 20x−24=36x+8.
Subtract 20x: Solve for x by first subtracting 20x from both sides: −24=16x+8.
Subtract 8: Now subtract 8 from both sides: −32=16x.
Divide by 16: Finally, divide both sides by 16 to solve for x: x=−1632.
Simplify Fraction: Simplify the fraction to get the final answer: x=−2.
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