2. 2.4 variables and equations September 12, 2011
equation - mathematical sentence with an equal sign
Types of equations we'll see:
9 + 2 = 11 numerical expression = numerical expression
x + 7 = 37 variable expression = numerical expression
a + (-3) = 2a + 5 variable expression = variable expression
HW pg. 135 odds 2
3. 2.4 variables and equations September 12, 2011
open sentence - equation with one or more variables
State whether each equation is true or false, and open sentence.
6 + 12 = 18
6=4+3
6 = - 3 + 5y
HW pg. 135 odds 3
4. 2.4 variables and equations September 12, 2011
Write an equation for
Nine times the opposite of five is forty-five.
Is this T, F, or open?
HW pg. 135 odds 4
5. 2.4 variables and equations September 12, 2011
Write an equation for
twenty minus x is three
Is this T, F, or open?
HW pg. 135 odds 5
6. 2.4 variables and equations September 12, 2011
solution of an equation - a value of a variable that makes an equation true.
Is 30 a solution of the equation 170 + x = 200?
HW pg. 135 odds 6
7. 2.4 variables and equations September 12, 2011
Is the given number a solution of the equation?
8 + t = 2t; 1
HW pg. 135 odds 7
8. 2.4 variables and equations September 12, 2011
A diver's equipment weighs 35 lb.
The diver plus the equipment weighs 165 lb.
Can the diver's weight be 200 lb?
HW pg. 135 odds 8