Transcript Plenary

Plenary
When you write algebraic
expressions, use +, -, and =
signs. For division, use / , the
same way you know that when
you see a fraction, it means to
divide the top number by the
bottom number.
2. For multiplication, write the expression
with no symbol or sign between them as
the X (multiplication) symbol can be
confused with the variable x. For
example 3 times the variable y should be
written 3y. You can also use parentheses
to indicate multiplication. This is
especially useful in longer problems
such as (3y)(4-2x).
3. When you want to multiply
something AFTER another
expression has been done first,
use parenthesis. For example, if
you want to add x and y and
THEN multiply the result by 7,
write it this way: 7(x + y).
4. To translate from language to
a math expression, read the
sentence carefully. Then decide
what operations it will take to
reach a solution. Write this into
an algebraic expression.

Something new:
1.
To take something OUT of parenthesis,
do the operation one number at a time.
For example, 7(x+y). First, multiply 7
times x. Then multiply 7 times y. The
result is 7x + 7y.
 Something
new:
2. When you solve for x, you want to
"isolate" the x on one side of the
equal sign. To do this, use the
opposite sign of the number you
want to move and do the same
thing to BOTH sides of the
equation.

Something new:
For example:
8x + 2 = 50
8x + 2 - 2 = 50 - 2 (Subtract 2 from both sides of the
= sign)
8x = 48 (Divide by 8 to solve because that is
opposite of multiplication)
x=6
And now a fun problem to
make you really think. Solve
using algebra. Translate into
an expression and solve.
You can do it!