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Tagged: Changing The Subject, equations, Formulae
Change the subject of the equation to r: S = 500(1 – r).
$$\frac{S}{500} = 1 – r$$ divide both sides by 500
$$\frac{S}{500} +r = 1$$ add r to both sides
$$r = 1-\frac{S}{500}$$ subtract S over 500 from both sides
Make v the subject of the formula: u = pq + vt^{2}.
u = pq + vt^{2}. u – pq = vt^{2} subtract pq from both sides
$$\frac{u-pq}{t^2}=v$$ divide both side by t^{2}
$$v=\frac{u-pq}{t^2}$$
Given that $$\frac{b^2}{a^2}= 1-e^2$$ , a = 4 and e = 0.3, find the value of b correct to two decimal places.
$$\frac{b^2}{4^2}=1-0.3^2$$
$$\frac{b^2}{16}=0.91$$
$$\frac{b^2}{16}^{\times\cancel{16}}=0.91^{\times16}$$
b² = 14.56
b = √14.56
b = 3.82