1The table below shows some corresponding values of x and (y−3)2 where y is positive.\begin{tabular}{|c|c|c|c|}\hlinex & 2 & 8 & 32 \\\hline(y−3)2 & 4 & 16 & 64 \\\hline\end{tabular}x(i) Explain with evidence whether x is directly proportional to (y−3)2.(ii) Express x in terms of y.(iii) Find the value of x when (y−3)21.(iv) Find the value of y when (y−3)23.
Q. 1The table below shows some corresponding values of x and (y−3)2 where y is positive.\begin{tabular}{|c|c|c|c|}\hlinex & 2 & 8 & 32 \\\hline(y−3)2 & 4 & 16 & 64 \\\hline\end{tabular}x(i) Explain with evidence whether x is directly proportional to (y−3)2.(ii) Express x in terms of y.(iii) Find the value of x when (y−3)21.(iv) Find the value of y when (y−3)23.
Check Ratios: (i) To check if x is directly proportional to (y−3)2, look at the ratios of x to (y−3)2. For x=2, (y−3)2=4, ratio is 42=0.5. For x=8, (y−3)2=16, ratio is 168=0.5. For (y−3)20, (y−3)21, ratio is (y−3)22. Since the ratios are constant, x is directly proportional to (y−3)2.
Find Constant: (ii) Since x is directly proportional to (y−3)2, we can write x as a multiple of (y−3)2. Let's use the first set of values to find the constant of proportionality, k. x=k∗(y−3)22=k∗4k=42k=0.5 So, x=0.5∗(y−3)2.
Substitute and Solve: (iii) To find x when y=1.2, substitute y=1.2 into x=0.5⋅(y−3)2. x=0.5⋅(1.2−3)2 x=0.5⋅(−1.8)2 x=0.5⋅3.24 x=1.62
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