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
Two halfs equal one whole. think of it like this, an orange cut in half leaves you with two halfs, put them together and you have a whole. simple. multiplying by 2 just means adding a number two times.
1 half plus one half= 2halves= 1 whole
1half x 2= 2 halves=1 whole
<em>Answer:</em>
<em>n = 12</em>
<em>Step-by-step explanation:</em>
<em>85%×n = 10.2</em>
<em>85n/100 = 10.2</em>
<em>85n = 1020</em>
<em>n = 1020 : 85</em>
<em>n = 12</em>
Step-by-step explanation:
[1-2 -4+6 3-2 5+4]
[-1 2 1 9]
7^4 or seven to the fourth power because 7 is being multiplied by 7 when you raise it to a power.
