Answer:
Step-by-step explanation:
3. We want to solve using properties;
It simply involve trying to reduce numbers to their simpliest form to make multiplication and addition easy without using calculator.
like; 21=20+1, 39=40-1 etc.
4. Given;
5(2x - 8) + 15 = -15
-15 -15 subtract 15 from each side
5(2x - 8) = -30
÷5 ÷5 divide both sides by 5
2x - 8 = -6
+8 +8 add 8 to each side
2x=2
÷2 ÷2 divide both sides by 3
x = 1
Checking:
5(2(1)-8) + 15 = -15
5(-6) + 15 = -15
-30 + 15 = -15
-15 = -15 Correct! x=1
Step-by-step explanation:
Given : AD=CD and
∠3=∠4
To prove : Line DB bisects ∠ABC
i.e.∠ABD=∠CBD
Proof : Consider ΔABD and ΔCBD,
and
and
So, ΔABD ≅ ΔCBD (By SAS criterion}
Hence , By CPCT (corresponding part of congruent triangle}
∠ABD=∠CBD
Therefore, Line DB bisects ∠ABC.
Answer:
x = -7
Step-by-step explanation:
Replace the x with -7 and add 4 to -7 to get -3. Then multiply by 7 to get -21.