**Choice D**

$$\frac{x}{72}=\frac{1\frac{3}{4}}{24} \\$$ $$ \Rightarrow x=5\frac{1}{4}$$

**Choice G**

$$\begin{bmatrix}2\times1+3\times2 & 2\times2+3\times1 \\2\times3-3\times1 & 2\times4-3\times2 \end{bmatrix}=\begin{bmatrix}8 & 7 \\3 & 2 \end{bmatrix}$$

**Choice D**

The speed of one motorcycle exceeds 4 times the speed of another motor cycle by 24 mph: 4g+24

**Choice H**

$$Driving \ time = \frac{1200}{50}=24 \\$$ $$ Unloading \ time = 12 \\$$ $$ \Rightarrow Total \ time=24+12+30=66=24+24+18$$

**Choice H**

Thus the other side is also 16; the remaining 2 sides are: $$\frac{80-16-16}{2}=24$$

**Choice E**

$$200x=500+20\times30 \\$$ $$ \Rightarrow x=5.5$$

**Choice B**

The length of the rectangle is w + 12; the area is $$w\cdot l=140 \\$$ $$ \Rightarrow w\cdot (w+12)=140$$

**Choice H**

$$\sqrt{(-8-4)^2+(4-9)^2}=\sqrt{169}$$

**Choice E**

(6,3+(7-3)+(7-3))=(6,11)

**Choice H**

$$Area = \pi r^2=\pi (\frac{6}{2})^2=9 …

**Choice D**

$$\frac{99+98+88\times(n-2)}{n}=91 \\$$ $$ \Rightarrow n=7$$

**Choice J**

Among the choices, only 60 …

**Choice A**

$$x^2-x-72=(x-9)(x+8)$$

**Choice F**

$$Volume=\pi r^2 h=\pi (8^2)(5) \\$$ …

**Choice E**

$$\sin C= \frac{AB}{AC} \\ $$ …

**Choice H**

$$\angle R= \angle P=54° \\ …

**Choice B**

g(1) > 0

g(2) > 0

g(3) …

**Choice J**

$$b=3n \\$$ $$\Rightarrow \frac{1}{b}+\frac{1}{n}=\frac{1}{3n}+\frac{1}{n}=\frac{...}{3n}$$

**Choice E**

$$g=b+15 \\$$ $$ r=g+24=b+39 \\$$ …

**Choice K**

$$(5-2)\times 180°-70°-100°-110°-135°=125°$$

**Choice A**

$$WD=\frac{6}{2}=3 \\$$ $$ WA=\frac{8}{2}=4 \\$$ …

**Choice G**

OS=2r

Thus S(0, -2r)

**Choice B**

‘x varies directly with y’ …

**Choice G**

$$(|x|-2)(|x|+1)=0 \\$$ $$ \Rightarrow |x|=2 …

**Choice B**

The line ST is going …

**Choice H**

$$(\frac{1+4}{2},\frac{2+0}{2})=(\frac{5}{2},1)$$

**Choice D**

$$\tan \angle STR = \frac{SR}{RT}=\frac{2}{3}$$

**Choice F**

SR is the radius which …

**Choice D**

A cube has 6 sides. …

**Choice K**

y=-3-5=-8

**Choice B**

$$y=\frac{4}{3}x+\frac{2}{3} \\$$ $$ \Rightarrow slope=\frac{4}{3} …

**Choice K**

K: |x|=x

When x is …

**Choice A**

$$Area = \frac{AB+CD}{2}\cdot EF=\frac{8+12}{2}\cdot 6=60$$

**Choice J**

$$x^2={\sqrt{a}}^2=a$$

**Choice A**

$$\tan\alpha=\frac{50-5}{80}=\frac{45}{80}$$

**Choice G**

Firstly, one need to identify …

**Choice A**

$$\frac{3}{6}\cdot\frac{1}{6}=\frac{1}{12}$$

**Choice H**

$$Area = (18-2x)(12-x)=2x^2-42x_216$$

**Choice B**

**Choice K**

$$\frac{x^{24}}{x^6}\cdot x^2=x^{24+2-6}=x^{20}$$

**Choice A**

$$a\cdot b=-48 \\$$ $$ a+b=0 …

**Choice K**

$$Area = 6\times(4+6+4)=84$$

**Choice A**

$$\frac{6}{7}\times \frac{1}{3}\times \frac{1}{100}=\frac{1}{350}$$ Choice A.

**Choice G**

$$(x+3)^2=x^2+3 \\ $$ $$\Rightarrow x^2+6x+9=x^2+3 …