Math Y8Y9 Change Subject of Algebra & Rearrange

What is the first step in rearranging a formula?

• Ignore the formula

• Solve for the variable first

• Identify the variable you want to isolate on one side of the equation.

• Flip the equation

If y = 3x + 5, what is x in terms of y?

• x = (y - 5) / 3

• x = (y + 3) / 5

• x = (y - 3) / 5

• x = (y + 5) / 3

Mathematical Equivalence

ON

In the formula V = lwh, how can you rearrange it to make w the subject?

• w = V + lh

• w = V - lh

• w = V * lh

• w = V / lh

If P = 2l + 2w, how can you express l in terms of P and w?

• l = (P - 2w) / 2

• l = P + 2w

• l = P - 2w

• l = P / 2w

What is the process of changing the subject of a formula called?

• Rearranging or solving for a specific variable

• Flipping the formula upside down

• Substituting numbers into the formula

• Rearranging or solving for a random variable

Given the formula C = 2πr, how can you rearrange it to make r the subject?

• r = 2π / C

• r = C - 2π

• r = C / 2π

• r = C * 2π

If A = πr², how can you change the subject to find r?

• r = 2π/A

• r = √(A)

• r = A/π

• r = √(A/π)

How can you change the subject of the formula T = 2π√(l/g) to make l the subject?

• l = g * (T / 2π)^2

• l = (T / 2π)^2 / g

• l = g * (T / (2π))^2

• l = g * T / 2π

a(x + c) = b(x + d)

• X = bd - ac / a - b
• X = db + gh / f - f
• X = fd - ac / s - d
• X = ac + br / d - s