Find AB Given A=[7 -5 0]
[1 3 8]

B= [-4 5]
[2 -7]
[3 1]

(1) The Given Expression:

-282 - (+1017)

= -282 - 1017

= -1299 (Option B)

(2) The total balance = $35

One check = $10

Three checks = 3 * 9 =9=27

Balance now = Total balance - One check + Three check = 35 -35−10 - $27 = -2 (Option A)

(3) The given expression:

3b – 7 < 32

Add 7 on both sides:

3b -7 + 7 < 32 + 7

3b < 39

Divide by 3 on both sides:

\frac{3b}{3} < \frac{39}{3}

3

3b

<

3

39

b < 13 (Option A)

(4) The given expression:

4m + 9 + 5m – 12 = 42

9m = 42 + 12 - 9

9m = 45

Divide both sides with 9:

\begin{gathered} \frac{9m}{9} =\frac{45}{9} \\ m=5 \end{gathered}

9

9m

=

9

45

m=5

The correct answer is m=5 (Option D)

(5) The given expression:

13 + (–12) – (–5)

= 13 - 12 + 5

= 6 (Option D)

(6) Mathematically, we can write "four times a number plus 3 is 11" as:

4x + 3 = 11

Where,

x = The number we require

4x = 11 - 3

4x = 8

x = 2 (Option B)

(7) The given expression:

12p + 7 > 139

Subtract 7 on both sides:

12p + 7 - 7 > 139 -7

12p > 132

Divide 12 on both sides:

\frac{12p}{12} > \frac{132}{12}

12

12p

>

12

132

p > 11 (Option A)

(8) The given equation:

7x = 42

Divide the equation with 7 on both sides:

\frac{7x}{7} =\frac{42}{7}

7

7x

=

7

42

x = 6 (Option B)

(9) The given expression:

9h + 2 < –79

Subtract 2 on both sides:

9h + 2 - 2 < -79 - 2

9h < -81

h < -9 (Option A)

(10) The given equation:

D = ABC

Now divide both sides with AB on both sides:

\begin{gathered} \frac{D}{AB} =\frac{ABC}{AB} \\ C =\frac{D}{AB} \end{gathered}

AB

D

=

AB

ABC

C=

AB

D

Hence C = D ÷ AB (Option B)

(11) Given equation:

\frac{y}{9} + 5 = 0

9

y

+5=0

Subtract 5 on both sides:

\frac{y}{9} +5 -5 = 0 -5

9

y

+5−5=0−5

y = -5*9 = -45

y = -45 (Option B)

(12) Given equation:

12y = 132

Divide both sides by 12:

\frac{12y}{12} =\frac{132}{12}

12

12y

=

12

132

y = 11 (Option A)

(13) The given equation:

3q + 5 + 2q – 5 = 65

5q = 65

Divide both sides with 5 and simplify:

q = 13 (Option D)

(14) Given formula:

K = LMN

To find M, divide both sides with LN:

\begin{gathered} \frac{K}{LN} =\frac{LMN}{LN} \\ M = \frac{K}{LN} \end{gathered}

LN

K

=

LN

LMN

M=

LN

K

Hence the correct answer is M = \frac{K}{LN}M=

LN

K

(Option A)

(15) Given formula:

h/9 = 7

Multiply both sides with 9:

h = 7 * 9

h = 63 (Option C)

(16) Given expression:

4p + 9 + (-7p) + 2

4p + 9 -7p +2

-3p + 11 (Option C)

(17) The given formula:

16y = 164

Divide both sides with 16:

\begin{gathered} \frac{16y}{16} =\frac{164}{16} \\ y = 10\frac{1}{4} \end{gathered}

16

16y

=

16

164

y=10

4

1

Hence the correct answer is (Option C) y = 10\frac{1}{4}y=10

4

1

(18) Given equation:

4y + 228 = 352

Subtract both sides with 228:

4y + 228 - 228 = 352 - 228

4y = 124

Divide both sides by 4 and simplify:

y = 31 (Option D)

(19) The given formula:

E = IR

To find R, divide both sides with I:

R = E ÷ I (Option D)

(20) Given equation:

6y - 20 = 2y - 4

=> 6y - 2y = -4 + 20

=> 4y = 16

Divide both sides with 4 and simplify:

y = 4 (Option B)