Answer:
d) 86.2 degrees
x = 86.20°
Attached is the image used in the question;
Step-by-step explanation:
Applying the law of cosine;
Cos C = (a² + b² - c²)/2ab
Where;
Angle C = x
c = 13 ft
b = 9ft
a = 10ft
Substituting into the equation;
Cos x = (10² + 9² - 13²)/(2×10×9)
Cos x = 0.0667
x = cos⁻¹(0.0667)
x = 86.20°
X1= -1.683
X2=0.816
X3=0.6666
Use the FOLD method<span>
(a+b)(c+d)=ac+ad+bc+bd
</span><span>−12<span>s<span><span>^2 </span><span></span></span></span>+ 3st + 8ts − 2<span>t<span><span>^2</span><span>
</span></span></span></span>Collect like terms
-12{s}^{2}+(3st+8st)-2{t}^{2}
Simplify
<span>-12{s}^{2}+11st-2{t}^{2}<span>−12<span>s<span><span>2</span><span></span></span></span>+11st−2<span>t<span><span>2
The answer is = -12s^2 + 11st - 2t^2</span></span></span></span></span>
Answer:
i think its x = -14/19 Not 100% sure