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
It seems that some the work is already here, but I'd be glad to!! So for #3 which is 9x^2+15x, we can factor out both a 3 and an x (3x) so we know that 3x * 3x =9x^2 and 3x * 5 = 15x so once we take the 3x out of the equation, we are left with 3x(3x+5) and that's as far as you can factor.
For #4, we see that the common factor is 10m because 10m * 2n = 20mn and 10m * 3 = 30m so once we take 10m out of the original, it becomes 10m(2n-3)
For #5, this one the common factor is 4xy because 4xy * 2xy=8x^2y^2 and 4xy*x= 4x^2y and 4xy*3=12xy so once we take the 4xy out of the equation, it becomes 4xy(2xy-x-3)
Hope this helps!
Answer:
m<FAB = 75°
m<BAC = 105°
Step-by-step explanation:
First, find the value of x.
(13x - 3)° = (3x + 2)° + 55° (exterior angle theorem of a ∆)
Solve for x
13x - 3 = 3x + 2 + 55
13x - 3 = 3x + 57
Collect like terms
13x - 3x = 57 + 3
10x = 60
Divide both sides by 10
x = 6
✔️m<FAB = 13x - 3
Plug in the value of x
m<FAB = 13(6) - 3 = 78 - 3
m<FAB = 75°
✔️m<BAC = 180 - m<FAB (angles on a straight line/supplementary angles)
m<BAC = 180 - 75 (substitution)
m<BAC = 105°
Answer:
can u rewrite the questions
Step-by-step explanation: