Step-by-step explanation:
there are 2 similar triangles : ABE and DCE
that means they have the same angles, and the scaling factor from one triangle to the other is the same for every side.
and that means that
DE/AE = EC/BE (= DC/AB)
we know that
AE = AD + DE
BE = BC + EC
a.
so, we have actually
DE/(AD+DE) = EC/(BC+EC)
DE/(10+DE) = 8/(2+8) = 8/10 = 4/5
DE = 4(10+DE)/5
5DE = 4(10+DE) = 40 + 4DE
DE = 40 cm
b.
AD/DE = 3/5
BC/EC must be 3/5 too.
15/EC = 3/5
15 = 3EC/5
75 = 3EC
EC = 25 cm
Answer:
<h2><em>
2(3s-14)</em></h2>
Step-by-step explanation:
Given the angles ∠ABF=8s-6, ∠ABE = 2(s + 11), we are to find the angle ∠EBF. The following expression is true for the three angles;
∠ABF = ∠ABE + ∠EBF
Substituting the given angles into the equation to get the unknown;
8s-6 = 2(s + 11)+ ∠EBF
open the parenthesis
8s-6 = 2s + 22+ ∠EBF
∠EBF = 8s-6-2s-22
collect the like terms
∠EBF = 8s-2s-22-6
∠EBF = 6s-28
factor out the common multiple
∠EBF = 2(3s-14)
<em></em>
<em>Hence the measure of angle ∠EBF is 2(3s-14)</em>
$6.89
The book is $10. Minus the 35% discount ($10X0.35=$3.50). So the subtotal is $10-$3.50=$6.50.
Tax is 6%. So 0.06X$6.50=$0.39
The total including tax is $6.50+$0.39=$6.89
Answer:12
Step-by-step explanation: