Answer:
No
Step-by-step explanation:
Let's check the first statement with an example. 2 and 3 are positive numbers and their sum (5) is also positive so his first statement is true.
To check the second statement let's look at the negative numbers -1 and -8 for example. Their sum (-9) is also negative so his second statement is true.
To check the third statement let's look at the numbers 9 and -5. One is positive and one is negative, but their sum (4) is positive, so his third statement is false. However if we look at the numbers 4 and -7, their sum is negative so the third statement is partially false.
I believe the answer is
1.1-(-3.8)=4.9
Answer:
110°
Step-by-step explanation:
This quadrilateral have the same size in AD and CD, and BA and CA, so it means that, if you cut this figure in the middle (from B to D), the two triangles will be identical, and the sum of the internal angles of a triangle is 180°, so:
(110°÷2) + (30°÷2) + <C = 180°
55° + 15° + <C = 180°
70° +<C = 180°
<C = 180° - 70°
<C = 110°
And you can test it making the sum of the internal angles of the quadrilateral. The sum of the internal angles of a quadrilateral is 360°, and the angles A and C have the same measure because AD=CD and AB=BC, so:
<A + <B + <C + <D
110° + 110° + 110° + 30° = 360°