SaiBook.us Algebra

Home Course Section

Register Enroll

Step-3

Title: Calculate the equation

Grade: 8-a Lesson: S4-L5

Explanation: Hello Students, time to practice and review the steps for the problem.

Lesson Steps

Step	Type	Explanation	Answer
1	Problem	Calculate the equation \$ \|- 13x - 21 \| = \|- x \| \$
2	Formula:	By using formula	\$\| x \| = \| x \| \$
3	Hint	By removing mod we get(+) or (-)	\$x=x (or) x=-x \$
4	Step	By simplifying we get	\$ -13x - 21 = -x (or) -13x - 21 = -(- x) = x \$
5	Step	Move 'x' variable terms right hand side and constant terms left hand side	\$ -13x + x = 21 (or) -13x - x = 21 \$
6	Step	After simplification we get	\$ -12x = 21 (or) -14x = 21 \$
7	Step	Dividing on both sides '-12' and '-14'	\$ \cancel(-12)/\cancel(-12)x = \cancel21^7/\cancel(-12)^4 (or) \cancel(-14)/\cancel(-14)x = 21/(-14) \$
8	Step	After cancellation we get	\$ x = -7/4 (or) x = -21/14 \$
9		Answer	C

Step

Type

Explanation

Answer

Problem

Calculate the equation
\$ |- 13x - 21 | = |- x | \$

Formula:

By using formula

\$| x | = | x | \$

Hint

By removing mod we get(+) or (-)

\$x=x (or) x=-x \$

Step

By simplifying we get

\$ -13x - 21 = -x (or) -13x - 21 = -(- x) = x \$

Step

Move 'x' variable terms right hand side and constant terms left hand side

\$ -13x + x = 21 (or) -13x - x = 21 \$

Step

After simplification we get

\$ -12x = 21 (or) -14x = 21 \$

Step

Dividing on both sides '-12' and '-14'

\$ \cancel(-12)/\cancel(-12)x = \cancel21^7/\cancel(-12)^4 (or) \cancel(-14)/\cancel(-14)x = 21/(-14) \$

Step

After cancellation we get

\$ x = -7/4 (or) x = -21/14 \$

Answer