Answer:
Explanation:
10. From the given figure,
![(18)/(y)=sin60^(0)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ptkbjc4ke2gv3phcgi85bsp7id53r4dges.png)
![y=(36)/(√(3))](https://img.qammunity.org/2020/formulas/mathematics/middle-school/kdv7q7kpr7qad67jq9bv3t70urkb8my60y.png)
11. From the given figure,
![(12)/(y)=sin60^(0)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ek9x4s4pi2oflcqeta0cbd0pv4fwtamf80.png)
![y=\frac{12{*}2}{√(3)}=(24)/(√(3))](https://img.qammunity.org/2020/formulas/mathematics/middle-school/8hbenn3rfjdeteht1m0ly4s1vjbehg1hyg.png)
and
![(x)/(y)=cos60^(0)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/2uwrabp744k5qqlgr7uuhoe9shkoc30bkp.png)
![x=\frac{24}{√(3){*}2}=(12)/(√(3))](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ni0jmhbi0mmuvg3j6fgpw4i9c1ebjfit21.png)
12. The sides of an equilateral triangle has length=10 inches, therefore AB=BC=AC=10
Also, AD is the height of the given triangle,then BD=DC=5
From triangle ADC,
![(AC)^(2)=(AD)^(2)+(DC)^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/aae2ii43xg09uhf1cpgkp65g22q11ckxwi.png)
![100=(AD)^(2)+25](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ep5o1s7et97yje1c6jig35ukf0qmzos2ys.png)
![75=(AD)^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/kgv0k14so9p2ha59597b6qq8pbg0utk19y.png)
![AD=√(75)inches](https://img.qammunity.org/2020/formulas/mathematics/middle-school/b4x604evhz37nak99hxydqfdfa7srge4tz.png)
Hence, height of the triangle is
![√(75)inches](https://img.qammunity.org/2020/formulas/mathematics/middle-school/x85csoqz7r3rw1w6v4npvyn45w7lblovv2.png)
13. Height of the ramp from the ground is 8ft.
therefore, let BC=x
![(8)/(BC)=tan30^(0)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/whsoncios24vm1fiesfhak84ha8w1rp3nh.png)
![(8)/(x)=(1)/(√(3))](https://img.qammunity.org/2020/formulas/mathematics/middle-school/s8r4woaz5xpzn74m1pra5dhs98st79p3nv.png)
![x=8√(3)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/wwhj6rv10zeiqowlthtq1rkhscpz9yokbz.png)
14. Let BC=x and AB=y
then,
![(x)/(18)=cos30^(0)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/gyzy7q076fxcvdj1e8z98jmse9tqlcfbdp.png)
![x=18{*}(√(3))/(2)=9√(3)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jluhht5evv7keb8rgn9trr3gptmo5gwmm2.png)
and
![(y)/(x)=tan30^(0)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/meib0eafhy5lshiulngy0nome6kkvg429f.png)
![y=9](https://img.qammunity.org/2020/formulas/mathematics/high-school/lbe7cetkyupszfsu17lale83fwrr9twib5.png)
The perimeter of triangle is=Sum of all the sides=AB+BC+AC=
![9√(3)+9+18= 9√(3)+27=9(1.73)+27=42.57 inches](https://img.qammunity.org/2020/formulas/mathematics/middle-school/81kq4ptndn3p4uqqpgy85mxst84ri7z8d6.png)
15. Let AB be the height of the tree, then
![(AB)/(8)=tan30^(0)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/r01yxwg05zxl1gkmq6n0uiltszckx2edbd.png)
![AB=8{*}(1)/(√(3))=(8)/(1.73)=4.62m](https://img.qammunity.org/2020/formulas/mathematics/middle-school/6772gcw9kn7q2tl55cgfep7pec5wq0tokf.png)
16. According to question,
![(h)/(24)=sin30^(0)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/yey2v8r5p16o7xevjy6riq3072iuhpi42x.png)
![h=(24)/(2)=12ft](https://img.qammunity.org/2020/formulas/mathematics/middle-school/nhl29vtvo8sax507yw74uthukr5txtf9kt.png)