11.36 would be the answer
<h2>(1)</h2><h2> =(a+b)(3c-d)</h2><h2> =a(3c-d)+b(3c-d)</h2><h2> =3ac-ad+3bc-bd</h2>
<h2>(2)</h2><h2> =(a-b)(c+2d)</h2><h2> =a(c+2d)-b(c+2d)</h2><h2> =ac+2ad-bc-2bd</h2>
<h2>(3)</h2><h2> =(a-b)(c-2d)</h2><h2> =a(c-2d)-b(c-2d)</h2><h2> =ac-2ad-bc+2bd</h2>
<h2>(4)</h2><h2> =(2a+b)(c-3d)</h2><h2> =2a(c-3d)+b(c-3d)</h2><h2> =2ac-6ad+bc-3bd</h2>
Clara will she will have 16 phone calls while Toby will have 15
(X-5)2+3(X-5)+9 = 0
let expand the equation
(x)x2-(5)x2 + 3(x)-3(5) + 9 = 0
2x-10+3x-15+9=0
collect like terms
2x+3x-10-15+9 =0
5x-10-6 =0
5x-16=0
5x=0+16
5x=16
divide both side by 5 we have
x=16/5