Answer:
1. $3.84
2. $2. 30
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
A. Sin 42=0.669
Cos=52=0.617
B. Sin 90=1
cos 90=0
C. cos30=0.866
sin 70=0.940
D. sin80=0.985
cos 10=0.985
Answer:
13 and -14 satisfy this condition
Step-by-step explanation:
Let's represent that number as x
and the square of x is x^2
So,
x + x^2 = 182
Subtract 182 from both sides
x + x^2 - 182 = 182 - 182
x + x^2 - 182 = 0
rearrange the quadratic equation
x^2 + x -182 = 0
let's use the quadratic formula
or 
a = 1, b = 1, c = -182
or 
or 
or 
or 
or 
13 or - 14
Lets check
13 + 13^2 = 13 + 169
= 182
Also,
-14 + (-14^2) = -14 + 196
= 182
Answer:
Given: In parallelogram ABCD, AC=BD
To prove : Parallelogram ABCD is rectangle.
Proof : in △ACB and △BDA
AC=BD ∣ Given
AB=BA ∣ Common
BC=AD ∣ Opposite sides of the parallelogram ABCD
△ACB ≅△BDA∣SSS Rule
∴∠ABC=∠BAD...(1) CPCT
Again AD ∥ ∣ Opposite sides of parallelogram ABCD
AD ∥BC and the traversal AB intersects them.
∴∠BAD+∠ABC=180∘ ...(2) _ Sum of consecutive interior angles on the same side of the transversal is
180∘
From (1) and (2) ,
∠BAD=∠ABC=90∘
∴∠A=90∘ and ∠C=90∘
Parallelogram ABCD is a rectangle.
