Simultaneous Addition
1. Let's solve the system by adding the equations to eliminate one variable.
2. Consider the system:
$$4x - y = 3$$
$$6x + y = 7$$
3. Add the two equations:
$$(4x - y) + (6x + y) = 3 + 7$$
$$4x - y + 6x + y = 10$$
$$10x = 10$$
4. Solve for $x$:
$$x = \frac{10}{10} = 1$$
5. Substitute $x = 1$ into the first equation:
$$4(1) - y = 3$$
$$4 - y = 3$$
$$-y = 3 - 4 = -1$$
$$y = 1$$
6. **Answer:** $x=1, y=1$
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1. Now solve the system:
$$3x - 5y = -2$$
$$4x + 5y = 9$$
2. Add the two equations to eliminate $y$:
$$(3x - 5y) + (4x + 5y) = -2 + 9$$
$$7x = 7$$
3. Solve for $x$:
$$x = \frac{7}{7} = 1$$
4. Substitute $x=1$ into the first equation:
$$3(1) - 5y = -2$$
$$3 - 5y = -2$$
$$-5y = -5$$
$$y = 1$$
5. **Answer:** $x=1, y=1$
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1. Solve:
$$3x - 2y = -3$$
$$3x + 2y = 9$$
2. Add the two equations:
$$(3x - 2y) + (3x + 2y) = -3 + 9$$
$$6x = 6$$
3. Solve for $x$:
$$x = \frac{6}{6} = 1$$
4. Substitute $x=1$ into the first:
$$3(1) - 2y = -3$$
$$3 - 2y = -3$$
$$-2y = -6$$
$$y = 3$$
5. **Answer:** $x=1, y=3$
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1. Solve:
$$4a - 7b = -3$$
$$3a + 7b = 10$$
2. Add the two equations:
$$(4a - 7b) + (3a + 7b) = -3 + 10$$
$$7a = 7$$
3. Solve for $a$:
$$a = \frac{7}{7} = 1$$
4. Substitute $a=1$ into the first:
$$4(1) - 7b = -3$$
$$4 - 7b = -3$$
$$-7b = -7$$
$$b = 1$$
5. **Answer:** $a=1, b=1$
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1. Solve:
$$-x - 3y = -7$$
$$x - 2y = 2$$
2. Add both equations:
$$(-x - 3y) + (x - 2y) = -7 + 2$$
$$-5y = -5$$
3. Solve for $y$:
$$y = \frac{-5}{-5} = 1$$
4. Substitute $y=1$ into the second equation:
$$x - 2(1) = 2$$
$$x - 2 = 2$$
$$x = 4$$
5. **Answer:** $x=4, y=1$
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1. Solve:
$$4m + g = -22$$
$$4m + 2g = -3$$
2. Subtract the first from the second:
$$(4m + 2g) - (4m + g) = -3 - (-22)$$
$$4m + 2g - 4m - g = 19$$
$$g = 19$$
3. Substitute $g=19$ into the first:
$$4m + 19 = -22$$
$$4m = -41$$
$$m = -\frac{41}{4}$$
4. **Answer:** $m = -\frac{41}{4}, g = 19$