The CENTRE for EDUCATION in MATHEMATICS and CONProblem of the WeekProblem CExponential Expressionstwo expressions:Expression A:72×7xExpression B:441×2yEt x and y are positive integers, find all ordered pairs (x,y) so that th Exprestion A is equal to the value of Expression B.A=B
Q. The CENTRE for EDUCATION in MATHEMATICS and CONProblem of the WeekProblem CExponential Expressionstwo expressions:Expression A:72×7xExpression B:441×2yEt x and y are positive integers, find all ordered pairs (x,y) so that th Exprestion A is equal to the value of Expression B.A=B
Factor out common factors: First, simplify the coefficients by factoring out common factors. 441 is 63 squared, and 63 is 9 times 7, so 441=9×7×7. Now we have 72×7x=9×7×7×2y.
Divide by 9: Divide both sides by 9 to simplify. 72÷9=8. So we get 8×7x=7×7×2y.
Isolate 7x: Now, divide both sides by 7 to isolate 7x on one side. 8×7x−1=7×2y.
Rewrite 8 as 23: We can see that 8 is 2 cubed, so we rewrite 8 as 23. Now we have 23×7(x−1)=7×2y.
Equate the exponents: Since the bases are now the same (2 and 7), we can equate the exponents. 3+(x−1)=y and x−1=1. So we have two equations: 3+x−1=y and x−1=1.
Solve for x: Solve the second equation for x. x−1=1 gives us x=2.
Substitute x into y: Substitute x=2 into the first equation to find y. 3+2−1=y gives us y=4.
Check the solution: Check if the ordered pair (x,y)=(2,4) satisfies the original equation. 72×72 should equal 441×24. Calculate both sides: 72×49=3528 and 441×16=7056. Oops, there's a mistake here, the calculations don't match.
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