Exercise II. 6 Make the letter in bold the subject of the formula. \( 1 a b+c=d \) \( \qquad \) \( \qquad \) \( \qquad \) \( 2 a b-c=d \) \( \qquad \) \( \qquad \) \( \qquad \) \( 3 \frac{1}{8} m+3=2 r \). \( \qquad \) \( \qquad \) \( \qquad \) \( 4 p-\frac{q}{r}=s \) \( \qquad \) \( \qquad \) \( \qquad \) \( 5 \frac{p}{-q}+r=-s \) \( \qquad \) \( \qquad \) \( \qquad \)

Certainly! Let's go through each equation and solve for the specified variable by making it **bold**. Since the original bold letters weren't specified, I'll assume we need to solve for the first variable in each equation. If you have different variables in mind, feel free to let me know! --- ### 1. \( a b + c = d \) **Solve for** \( \mathbf{a} \): \[ a b + c = d \] Subtract \( c \) from both sides: \[ a b = d - c \] Divide both sides by \( b \): \[ \mathbf{a} = \frac{d - c}{b} \] --- ### 2. \( a b - c = d \) **Solve for** \( \mathbf{a} \): \[ a b - c = d \] Add \( c \) to both sides: \[ a b = d + c \] Divide both sides by \( b \): \[ \mathbf{a} = \frac{d + c}{b} \] --- ### 3. \( \frac{1}{8} m + 3 = 2 r \) **Solve for** \( \mathbf{m} \): \[ \frac{1}{8} m + 3 = 2 r \] Subtract \( 3 \) from both sides: \[ \frac{1}{8} m = 2 r - 3 \] Multiply both sides by \( 8 \): \[ \mathbf{m} = 8(2 r - 3) = 16 r - 24 \] --- ### 4. \( p - \frac{q}{r} = s \) **Solve for** \( \mathbf{p} \): \[ p - \frac{q}{r} = s \] Add \( \frac{q}{r} \) to both sides: \[ p = s + \frac{q}{r} \] --- ### 5. \( \frac{p}{-q} + r = -s \) **Solve for** \( \mathbf{p} \): \[ \frac{p}{-q} + r = -s \] Subtract \( r \) from both sides: \[ \frac{p}{-q} = -s - r \] Multiply both sides by \( -q \): \[ \mathbf{p} = (-q)(-s - r) = q(s + r) \] --- Feel free to replace the bolded variable with another if you intended to solve for a different one in any of the equations!