<u>Answer-</u>
<em>The correct answer is</em>
<em>∠BDC and ∠AED are right angles</em>
<u>Solution-</u>
In the ΔCEA and ΔCDB,

As this common to both of the triangle.
If ∠BDC and ∠AED are right angles, then 
Now as
∠BCD = ∠ACE and ∠BDC = ∠AED,
∠DBC and ∠EAC will be same. (as sum of 3 angles in a triangle is 180°)
Then, ΔCEA ≈ ΔCDB
Therefore, additional information can be used to prove ΔCEA ≈ ΔCDB is ∠BDC and ∠AED are right angles.
Notice that
(1 + <em>x</em>)(1 + <em>y</em>) = 1 + <em>x</em> + <em>y</em> + <em>x y</em>
So we can add 1 to both sides of both equations, and we use the property above to get
<em>a</em> + <em>b</em> + <em>a b</em> = 76 ==> (1 + <em>a</em>)(1 + <em>b</em>) = 77
and
<em>c</em> + <em>d</em> + <em>c d</em> = 54 ==> (1 + <em>c</em>)(1 + <em>d</em>) = 55
Now, 77 = 7*11 and 55 = 5*11, so we get
<em>a</em> + 1 = 7 ==> <em>a</em> = 6
<em>b</em> + 1 = 11 ==> <em>b</em> = 10
(or the other way around, since the given relations are symmetric)
and
<em>c</em> + 1 = 5 ==> <em>c</em> = 4
<em>d</em> + 1 = 11 ==> <em>d</em> = 10
Now substitute these values into the desired quantity:
(<em>a</em> + <em>b</em> + <em>c</em> + <em>d</em>) <em>a</em> <em>b</em> <em>c</em> <em>d</em> = 72,000
Answer:
-5
Step-by-step explanation:
-2+(-3)
-2-3
-5
Answer:
4 cm
Step-by-step explanation:
prolly cus the 12 cm is the bottom and the 4 cm is one of the sides so the other one is 4 cm
Problem:
find line perpendicular to 4x+7y+3=0 passing through (-2,1).
Solution:
We will first find the general form of the perpendicular line.
The perpendicular line has the form
7x-4y+k=0 .........................(1)
by switching the coefficients of x and y, and switching the sign of one of the two coefficients. This way, the slope of (1) multiplied by that of the original equation is -1, a condition that the two lines are perpendicular. The value of k is to be determined from the given point (-2,1).
To find k, we substitute x=-2, y=1 into equation (1) and solve for k.
7(-2)-4(1)+k=0
=>
k=14+4=18
Therefore the required line is
7x-4y+18=0