Choice E
Draw the blue one twice, …
Choice J
$$3\ pieces=x,\ y,\ z$$ $$x=2y=2(2z)=4z$$ $$y=2z$$ $$\Rightarrow x+y+z=4z+2z+z=21$$ $$\Rightarrow 7z=21$$ $$\Rightarrow z=3$$ $$x=4z=12$$
Choice C
$$(8+3)2=22$$
Choice C
$$\triangle BCD is a 6-8-10 triangle.$$ $$\overline{BD}=10$$ $$\underline{AB}=\overline{BD}=\overline{AD}=10$$
Choice D
$$\Rightarrow\frac{S+T}{2}$$ $$=\frac{(4,10)+(6,-2)}{2}$$ $$=\frac{(10,8)}{2}$$ $$=(5,4)$$
Choice C
$$\frac{1}{a}=2$$ $$\frac{1}{b}=3$$ $$\frac{1}{2}(\frac{1}{a}+\frac{1}{b})$$ $$=\frac{1}{2}(2+3)$$ $$=\frac{5}{2}$$
Choice C
$$20\ mins=\frac{1}{3}\ hr$$ $$50\times\frac{1}{3}=16.666\approx17$$
Choice H
$$$1=100¢$$ $$0.40\times x+0.25\times(20-x)=6.95$$ $$0.4x+5-0.25x=6.95$$ $$0.15x=1.95$$ …
Choice B
$$3x-2y=6$$ $$-2y=6-3x$$ $$2y=3x-6$$ $$y=\frac{3}{2}x-3$$ $$y=mx+b$$ …
Choice G
$$\sin 6°=0.1045=\frac{?}{4}$$ $$?=0.1045\times4=0.418$$
Choice E
$$Level\ 1=4\times5$$ $$Level\ 2=4\times6$$ $$Level\ …
Choice J
$$F.\sqrt{-5^{2}}=5$$ $$G.\sqrt{-2^{2}}=2$$ $$H.\sqrt{\frac{1}{2}^{2}}=\frac{1}{2}$$ $$\frac{1}{2}\ is\ …
Choice B
$$16(16-6)(\frac{1}{2})=80$$
Choice K
$$x-y\lt0$$ $$Let\ x=1,\ y=2$$ $$F.\ …
Choice E
Move down two units, the …
Choice G
$$-6+7k \geq 3-8k$$ $$\Rightarrow 15k …
Choice C
$$\Rightarrow \overline{AB}=4\overline{GH}$$
Choice F
$$2\frac{1}{3}\times\frac{1}{2}=1\frac{1}{6}$$
Choice B
$$6+1\times x=3+1\frac{1}{2}x$$ $$3=\frac{1}{2}x$$ $$x=6$$
Choice K
$$\Rightarrow x^{3}-4x^{2}-x^{2}+5x+3x+6$$ $$\Rightarrow x^{3}-5x^{2}+8x+6$$
Choice A
$$\tan \theta=\frac{0.5}{1}$$ $$\Rightarrow \tan \theta=\frac{1}{2}$$ …
Choice G
Choice C
$$\pi r^{2}=16\pi $$
Choice K
Choice B
Choice F
Choice D
$$r=\frac{10}{2}=5$$ $$\pi r^{2}h=\pi 5^{2}h=1000$$ $$h=1000\div25\div\pi=\frac{40}{\pi}\approx\frac{40}{3.14}=12.73$$
Choice J
$$1-\frac{1}{12}\times3=\frac{9}{12}=\frac{3}{4}$$ $$\frac{3}{4}\times\frac{1}{5}=\frac{3}{20}$$
Choice A
$$x=\frac{-b\pm\sqrt{b^{2}-4ac}}{2a}$$ $$=\frac{-(-5)\pm\sqrt{(-5)^{2}-4(1)(3)}}{2(1)}$$ $$=\frac{5\pm\sqrt{25-4(1)(3)}}{2(1)}$$
Choice F
$$(9,-13)+(a,b)=2(1,-6)=(2,-12)$$ $$9+a=2\ \Rightarrow\ a=-7$$ $$-13+b=-12\ …
Choice B
Let the base of the …
Choice K
$$(0,-1)\Rightarrow G,\ K$$ $$(K). m=3,\ …
Choice D
$$(10+18)\times 3\times\frac{1}{2}=42$$
Choice G
$$C=99\times h$$ $$m=0.99$$
Choice D
$$4,10,25$$ $$10\div4=2.5$$ $$25\div10=2.5$$ $$25\times2.5=62.5$$
Choice J
$$64=x^{3}$$ $$x=4$$ $$Total\ surface\ area=4\times4\times6=96$$
Choice C
$$2\pi r=2 \pi(4)=8\pi$$ $$\frac{7 \pi}{8\pi}=\frac{315}{360}$$ …
Choice K
The equation for a circle …
Choice D
$$\frac{a}{\sin A}=\frac{b}{\sin B}=\frac{c}{\sin C}$$ $$\Rightarrow …
Choice F
$$The\ side\ of\ square1:1+l$$ $$The\ …
Choice E
$$If\ \ x\leq2\ , then\ …
Choice H
More than 6 rooms:25-10=15
6 …
Choice B
$$\Rightarrow (\cos x)^{2}=(-\frac{1}{3})^{2}=\frac{1}{9}$$ $$\frac{1}{9}=\frac{1+\cos 2x}{2}$$ …
Choice F
$$y=f(g(x))=\sqrt{10x+b}$$ $$(4,6)\Rightarrow 6=\sqrt{10\times4+b}$$ $$\Rightarrow 36=40+b$$ …
Choice A
Choice F
$$b^{2}\gt 0;$$ $$(c^{2})^{2}\gt 0;$$ $$\Rightarrow …