Algebra 1 Common Core Student Edition, Grade 8-9

Think ing Mathematically

Mathematical reasoning is the key to making sense of math and

solving problem s. Throughout the program you'll learn strategies to

develop mathematical reasoning habits.

Hello, I ’m Tyler.

These plan boxes will

help me f ig ure out

where to start.

M«l Ac Uncut the right'Uuog Two Paint* to Writ, on equation

How does the graph
help you w rit e an
eq uat ion?
Yo u c a n u s e t w o p o i n t s
on the line to find the
sl ope. Then use
point-slope form.

^CSSSSD Using Two Points to Write an Equation

W h a t is a n e q u a t i o n o f t h e l i n e a t t h e r i g h t?

You need the slope m,

so s ta rt w i t h th e s lo p e

formula.

Us e t h e g iv e n p o in ts to

find the slope.

Us e p o in t-s lo p e f o rm.

Use e ith er g iven p o in t fo r

(x], y 1). For e xam p le, you

can use (1 ,4 ).

• xVz 2 ~ Yi - Xj

m =-3 - 4 .—2 — 1 zl-1— 3 3

y - yi = m(x - x ^

y - 4 = |( x - 1)

The w orked-out problem s include

call-outs that reveal the strategies and

reasoning behind the solution. Look fo r

the b oxes la b e le d Pl an and Think.

The Think- W rit e probl ems model the

thinking behind each step o f a solution.

Wh*ii* 16 cMihwloK| Sotving a Two-Sfup equation al*3* 15?

Sue**!! fa*. ud*

»«*<*!< iMefcje.

15 * 15 Supty fur WfuIWI rtwti.

i j ) Got If? l,WhMl»ihc*otoitonofi- | -3»

• Paper per ad: • Paper for banner: 5 sheets 5 sheet


• Total paper: 18 sheets

The num ber o f adsyou can make W rite and solve an equation. Let thevariable represent the unknown.

i -’M tj S.*g on.

Other worked-out problems model a

problem-solving plan that includes the

steps o f stating w h a t yo u Know ,

id e n tifyin g w h a t you N e e d / a n d

developing a Plan.