To solve the system of equations
- \( 4h + 4s = 10 \)
- \( 7h + 5s = 15 \)
we can start by simplifying the first equation.
Step 1: Simplify the first equation
Divide the entire equation by 4:
\[ h + s = \frac{10}{4} \implies h + s = 2.5 \]
So, we can write this as:
\[ h + s = 2.5 \quad (1) \]
Step 2: Solve for \(s\)
From equation (1):
\[ s = 2.5 - h \quad (2) \]
Step 3: Substitute \(s\) in the second equation
Now substitute equation (2) into the second equation:
\[ 7h + 5(2.5 - h) = 15 \]
Now, distribute:
\[ 7h + 12.5 - 5h = 15 \]
Combining like terms gives:
\[ 2h + 12.5 = 15 \]
Step 4: Solve for \(h\)
Subtract 12.5 from both sides:
\[ 2h = 15 - 12.5 \] \[ 2h = 2.5 \] \[ h = \frac{2.5}{2} = 1.25 \]
Step 5: Substitute \(h\) back into equation (2)
Now substitute \(h\) back into equation (2) to find \(s\):
\[ s = 2.5 - 1.25 = 1.25 \]
Step 6: Write the final answer
Thus, the solutions are:
\[ h = 1.25 \] \[ s = 1.25 \]
So the final answer is:
\( h = $1.25 \)
\( s = $1.25 \)